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Array Range Queries to count Powerful numbers with updates

  • Last Updated : 15 Jun, 2021

Given an array of N integers, the task is to perform the following two operations on the given array: 
 

query(L, R): Print the number of Powerful numbers in the subarray from L to R. 
update(i, x) : update the value at index i to x, i.e arr[i] = x 
 

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A number N is said to be Powerful Number if, for every prime factor p of it, p2 also divides it.
Prerequisites: Powerful Number, Segment tree
Examples: 
 



Input: 
arr = {1, 12, 3, 8, 17, 9} 
Query 1: query(L = 1, R = 4) 
Query 2: update(i = 1, x = 9) 
Query 3: query(L = 1, R = 4) 
Output: 


Explanation: 
Query 1: Powerful numbers in range arr[1:4] is 8. 
Query 2: Powerful numbers in range arr[1:4] after update operation is 9 and 8. 
 

 

Approach:
Since we need to handle point updates and range queries so we will use a segment tree to solve the problem. 
 

  1. We will precompute all the Powerful numbers till the maximum value that arr[i] can take, say MAX
    The time complexity of this operation will be O(MAX * sqrt(MAX)) 
     
  2. Building the segment tree: 
    • The problem can be reduced to subarray sum using segment tree
       
    • Now we can build the segment tree where the leaf nodes will represent 1(when a number is a Powerful number) or 0(when a number is not a powerful number). All the internal nodes will have the sum of both of its children. 
       
  3. Point Updates: 
    • To update an element we need to look at the interval in which the element is and recurse accordingly on the left or the right child. If the element to be updated is a Powerful number then we update the leaf as 1, else 0. 
       
  4. Range Query: 
    • Whenever we get a query from L to R, then we can query the segment tree for the sum of nodes in range L to R, which in turn represents the number of Powerful numbers in the range L to R. 
       

Below is the implementation of the above approach: 
 

C++




// C++ Program to find the number
// of Powerful numbers in subarray
// using segment tree
#include <bits/stdc++.h>
using namespace std;
 
#define MAX 100000
 
// Size of segment tree = 2^{log(MAX)+1}
int tree[3 * MAX];
int arr[MAX];
bool powerful[MAX + 1];
 
// Function to check if the
// number is powerful
bool isPowerful(int n)
{
    // First divide the number
    // repeatedly by 2
    while (n % 2 == 0)
    {
        int power = 0;
        while (n % 2 == 0)
        {
            n /= 2;
            power++;
        }
 
        // If only 2^1 divides
        // n (not higher powers),
        // then return false
        if (power == 1)
            return false;
    }
 
    // If n is not a power of 2 then
    // this loop will execute
    // repeat above process
    for (int factor = 3; factor
         <= sqrt(n); factor += 2)
    {
        // Find highest power of
        // "factor" that divides n
        int power = 0;
        while (n % factor == 0)
        {
            n = n / factor;
            power++;
        }
 
        // If only factor^1 divides n
        // (not higher powers),
        // then return false
        if (power == 1)
            return false;
    }
 
    // n must be 1 now if it is not
    // a prime numenr. Since prime
    // numbers are not powerful,
    // we return false if n is not 1.
    return (n == 1);
}
 
// Function to build the array
void BuildArray(int input[], int n)
{
    for (int i = 0; i < n; i++)
    {
        // Check if input[i] is
        // a Powerful number or not
        if (powerful[input[i]])
            arr[i] = 1;
 
        else
            arr[i] = 0;
    }
    return;
 
}
 
// A utility function to get the middle
// index from corner indexes.
int getMid(int s, int e)
{
    return s + (e - s) / 2;
}
 
/* A recursive function that constructs
 Segment Tree for array[ss..se].
 
si --> Index of current node in the
       segment tree. Initially 0 is
       passed as root is always
       at index 0.
ss & se --> Starting and ending indexes
            of the segment represented by
            current node, i.e., st[index]
*/
void constructSTUtil(int si, int ss,
                     int se)
{
    if (ss == se) {
        // If there is one element
        // in array
        tree[si] = arr[ss];
        return;
    }
 
    // If there are more than one elements,
    // then recur for left and right subtrees
    // and store the sum of the two
    // values in this node
    else {
        int mid = getMid(ss, se);
         
        constructSTUtil(2 * si + 1,
                        ss, mid);
         
        constructSTUtil(2 * si + 2,
                        mid + 1, se);
         
        tree[si] = tree[2 * si + 1]
                  + tree[2 * si + 2];
    }
}
 
/* A recursive function to update the
nodes which have the given index
in their range.
 
si --> Index of current node in the segment tree.
       Initially 0 is passed as root is always
       at index 0.
ss & se --> Starting and ending indexes of the
            segment represented by current node,
            i.e., st[index]
 
ind --> Index of array to be updated
 
val --> The new value to be updated
 
*/
void updateValueUtil(int si, int ss, int se,
                     int idx, int val)
{
    // Leaf node
    if (ss == se) {
        tree[si] = tree[si] - arr[idx] + val;
        arr[idx] = val;
    }
    else {
        int mid = getMid(ss, se);
         
        // If idx is in the left child,
        // recurse on the left child
        if (ss <= idx and idx <= mid)
            updateValueUtil(2 * si + 1, ss,
                            mid, idx, val);
 
        // If idx is in the right child,
        // recurse on the right child
        else
            updateValueUtil(2 * si + 2, mid + 1,
                            se, idx, val);
 
        // Internal node will have the sum
        // of both of its children
        tree[si] = tree[2 * si + 1]
                   + tree[2 * si + 2];
    }
}
 
/* A recursive function to get the number
of Powerful numbers in a given
range of array indexes
 
si --> Index of current node in the segment tree.
       Initially 0 is passed as root is always
       at index 0.
ss & se --> Starting and ending indexes of the
            segment represented by current node,
            i.e., st[index]
l & r --> Starting and ending indexes of
          query range
 
 
 */
int queryPowerfulUtil(int si, int ss, int se,
                      int l, int r)
{
    // If segment of this node is
    // outside the given range
    if (r < ss or se < l) {
        return 0;
    }
    // If segment of this node is a part
    // of given range, then return the
    // number of composites
    // in the segment
    if (l <= ss and se <= r) {
        return tree[si];
    }
 
    // If a part of this segment
    // overlaps with the given range
    int mid = getMid(ss, se);
    int p1 = queryPowerfulUtil(2 * si + 1,
                               ss, mid, l,
                               r);
    int p2 = queryPowerfulUtil(2 * si + 2,
                               mid + 1,
                               se, l, r);
    return (p1 + p2);
}
 
void queryPowerful(int n, int l, int r)
{
    printf("Number of Powerful numbers between %d to %d = %d\n",
           l, r, queryPowerfulUtil(0, 0,
                                   n - 1,
                                   l, r));
}
 
void updateValue(int n, int ind, int val)
{
    // If val is a Powerful number
    // we will update 1 in tree
    if (powerful[val])
        updateValueUtil(0, 0, n - 1,
                        ind, 1);
    else
        updateValueUtil(0, 0, n - 1,
                        ind, 0);
}
 
void precomputePowerful()
{
 
    memset(powerful, false,
           sizeof(powerful));
 
    // Computing all Powerful
    // numbers till MAX
    for (int i = 1; i <= MAX; i++)
    {
        // If the number is
        // Powerful make
        // powerful[i] = true
        if (isPowerful(i))
            powerful[i] = true;
    }
}
 
// Driver Code
int main()
{
    // Precompute all the powerful
    // numbers till MAX
    precomputePowerful();
 
    // Input array
    int input[] = { 4, 5, 18, 27, 40, 144 };
     
    // Size of Input array
    int n = sizeof(input) / sizeof(input[0]);
 
    // Build the array.
    BuildArray(input, n);
     
    // Build segment tree from
    // given array
    constructSTUtil(0, 0, n - 1);
 
    // Query 1: Query(L = 0, R = 3)
    int l = 0, r = 3;
    queryPowerful(n, l, r);
 
    // Query 2: Update(i = 1, x = 9),
    // i.e Update input[i] to x
    int i = 1;
    int val = 9;
    updateValue(n, i, val);
 
    // Query 3: Query(L = 0, R = 3)
    queryPowerful(n, l, r);
 
 
    return 0;
}

Java




// Java program to find the number
// of Powerful numbers in subarray
// using segment tree
import java.util.*;
 
class GFG{
 
static final int MAX = 100000;
 
// Size of segment tree = 2^{log(MAX)+1}
static int []tree = new int[3 * MAX];
static int []arr = new int[MAX];
static boolean []powerful = new boolean[MAX + 1];
 
// Function to check if the
// number is powerful
static boolean isPowerful(int n)
{
     
    // First divide the number
    // repeatedly by 2
    while (n % 2 == 0)
    {
        int power = 0;
        while (n % 2 == 0)
        {
            n /= 2;
            power++;
        }
 
        // If only 2^1 divides
        // n (not higher powers),
        // then return false
        if (power == 1)
            return false;
    }
 
    // If n is not a power of 2 then
    // this loop will execute
    // repeat above process
    for(int factor = 3;
            factor <= Math.sqrt(n);
            factor += 2)
    {
         
        // Find highest power of
        // "factor" that divides n
        int power = 0;
        while (n % factor == 0)
        {
            n = n / factor;
            power++;
        }
 
        // If only factor^1 divides n
        // (not higher powers),
        // then return false
        if (power == 1)
            return false;
    }
 
    // n must be 1 now if it is not
    // a prime numenr. Since prime
    // numbers are not powerful,
    // we return false if n is not 1.
    return (n == 1);
}
 
// Function to build the array
static void BuildArray(int input[], int n)
{
    for(int i = 0; i < n; i++)
    {
         
        // Check if input[i] is
        // a Powerful number or not
        if (powerful[input[i]])
            arr[i] = 1;
 
        else
            arr[i] = 0;
    }
    return;
}
 
// A utility function to get the middle
// index from corner indexes.
static int getMid(int s, int e)
{
    return s + (e - s) / 2;
}
 
/* A recursive function that constructs
Segment Tree for array[ss..se].
 
si -. Index of current node in the
    segment tree. Initially 0 is
    passed as root is always
    at index 0.
ss & se -. Starting and ending indexes
            of the segment represented by
            current node, i.e., st[index]
*/
static void constructSTUtil(int si, int ss,
                            int se)
{
    if (ss == se)
    {
         
        // If there is one element
        // in array
        tree[si] = arr[ss];
        return;
    }
 
    // If there are more than one elements,
    // then recur for left and right subtrees
    // and store the sum of the two
    // values in this node
    else
    {
        int mid = getMid(ss, se);
         
        constructSTUtil(2 * si + 1,
                        ss, mid);
         
        constructSTUtil(2 * si + 2,
                        mid + 1, se);
         
        tree[si] = tree[2 * si + 1] +
                   tree[2 * si + 2];
    }
}
 
/* A recursive function to update the
nodes which have the given index
in their range.
 
si -. Index of current node in the segment tree.
    Initially 0 is passed as root is always
    at index 0.
ss & se -. Starting and ending indexes of the
            segment represented by current node,
            i.e., st[index]
 
ind -. Index of array to be updated
 
val -. The new value to be updated
 
*/
static void updateValueUtil(int si, int ss, int se,
                            int idx, int val)
{
     
    // Leaf node
    if (ss == se)
    {
        tree[si] = tree[si] - arr[idx] + val;
        arr[idx] = val;
    }
    else
    {
        int mid = getMid(ss, se);
         
        // If idx is in the left child,
        // recurse on the left child
        if (ss <= idx && idx <= mid)
            updateValueUtil(2 * si + 1, ss,
                            mid, idx, val);
 
        // If idx is in the right child,
        // recurse on the right child
        else
            updateValueUtil(2 * si + 2, mid + 1,
                            se, idx, val);
 
        // Internal node will have the sum
        // of both of its children
        tree[si] = tree[2 * si + 1] +
                   tree[2 * si + 2];
    }
}
 
/* A recursive function to get the number
of Powerful numbers in a given
range of array indexes
 
si -. Index of current node in the segment tree.
    Initially 0 is passed as root is always
    at index 0.
ss & se -. Starting and ending indexes of the
            segment represented by current node,
            i.e., st[index]
l & r -. Starting and ending indexes of
        query range
 
*/
static int queryPowerfulUtil(int si, int ss,
                             int se, int l, int r)
{
     
    // If segment of this node is
    // outside the given range
    if (r < ss || se < l)
    {
        return 0;
    }
     
    // If segment of this node is a part
    // of given range, then return the
    // number of composites
    // in the segment
    if (l <= ss && se <= r)
    {
        return tree[si];
    }
 
    // If a part of this segment
    // overlaps with the given range
    int mid = getMid(ss, se);
    int p1 = queryPowerfulUtil(2 * si + 1,
                               ss, mid, l,
                               r);
    int p2 = queryPowerfulUtil(2 * si + 2,
                                  mid + 1,
                                 se, l, r);
    return (p1 + p2);
}
 
static void queryPowerful(int n, int l, int r)
{
    System.out.printf("Number of Powerful numbers " +
                      "between %d to %d = %d\n", l, r,
                      queryPowerfulUtil(0, 0, n - 1,
                                        l, r));
}
 
static void updateValue(int n, int ind, int val)
{
     
    // If val is a Powerful number
    // we will update 1 in tree
    if (powerful[val])
        updateValueUtil(0, 0, n - 1,
                        ind, 1);
    else
        updateValueUtil(0, 0, n - 1,
                        ind, 0);
}
 
static void precomputePowerful()
{
    Arrays.fill(powerful, false);
     
    // Computing all Powerful
    // numbers till MAX
    for(int i = 1; i <= MAX; i++)
    {
         
        // If the number is
        // Powerful make
        // powerful[i] = true
        if (isPowerful(i))
            powerful[i] = true;
    }
}
 
// Driver Code
public static void main(String[] args)
{
     
    // Precompute all the powerful
    // numbers till MAX
    precomputePowerful();
 
    // Input array
    int input[] = { 4, 5, 18, 27, 40, 144 };
     
    // Size of Input array
    int n = input.length;
 
    // Build the array.
    BuildArray(input, n);
     
    // Build segment tree from
    // given array
    constructSTUtil(0, 0, n - 1);
 
    // Query 1: Query(L = 0, R = 3)
    int l = 0, r = 3;
    queryPowerful(n, l, r);
 
    // Query 2: Update(i = 1, x = 9),
    // i.e Update input[i] to x
    int i = 1;
    int val = 9;
    updateValue(n, i, val);
 
    // Query 3: Query(L = 0, R = 3)
    queryPowerful(n, l, r);
}
}
 
// This code is contributed by amal kumar choubey

C#




// C# program to find the number
// of Powerful numbers in subarray
// using segment tree
using System;
class GFG{
 
static readonly int MAX = 100000;
 
// Size of segment tree = 2^{log(MAX)+1}
static int []tree = new int[3 * MAX];
static int []arr = new int[MAX];
static bool []powerful = new bool[MAX + 1];
 
// Function to check if the
// number is powerful
static bool isPowerful(int n)
{
     
    // First divide the number
    // repeatedly by 2
    while (n % 2 == 0)
    {
        int power = 0;
        while (n % 2 == 0)
        {
            n /= 2;
            power++;
        }
 
        // If only 2^1 divides
        // n (not higher powers),
        // then return false
        if (power == 1)
            return false;
    }
 
    // If n is not a power of 2 then
    // this loop will execute
    // repeat above process
    for(int factor = 3;
            factor <= Math.Sqrt(n);
            factor += 2)
    {
         
        // Find highest power of
        // "factor" that divides n
        int power = 0;
        while (n % factor == 0)
        {
            n = n / factor;
            power++;
        }
 
        // If only factor^1 divides n
        // (not higher powers),
        // then return false
        if (power == 1)
            return false;
    }
 
    // n must be 1 now if it is not
    // a prime numenr. Since prime
    // numbers are not powerful,
    // we return false if n is not 1.
    return (n == 1);
}
 
// Function to build the array
static void BuildArray(int []input, int n)
{
    for(int i = 0; i < n; i++)
    {
         
        // Check if input[i] is
        // a Powerful number or not
        if (powerful[input[i]])
            arr[i] = 1;
 
        else
            arr[i] = 0;
    }
    return;
}
 
// A utility function to get the middle
// index from corner indexes.
static int getMid(int s, int e)
{
    return s + (e - s) / 2;
}
 
/* A recursive function that constructs
Segment Tree for array[ss..se].
 
si -. Index of current node in the
    segment tree. Initially 0 is
    passed as root is always
    at index 0.
ss & se -. Starting and ending indexes
            of the segment represented by
            current node, i.e., st[index]
*/
static void constructSTUtil(int si, int ss,
                            int se)
{
    if (ss == se)
    {
         
        // If there is one element
        // in array
        tree[si] = arr[ss];
        return;
    }
 
    // If there are more than one elements,
    // then recur for left and right subtrees
    // and store the sum of the two
    // values in this node
    else
    {
        int mid = getMid(ss, se);
         
        constructSTUtil(2 * si + 1,
                        ss, mid);
         
        constructSTUtil(2 * si + 2,
                        mid + 1, se);
         
        tree[si] = tree[2 * si + 1] +
                   tree[2 * si + 2];
    }
}
 
/* A recursive function to update the
nodes which have the given index
in their range.
 
si -. Index of current node in the segment tree.
    Initially 0 is passed as root is always
    at index 0.
ss & se -. Starting and ending indexes of the
            segment represented by current node,
            i.e., st[index]
 
ind -. Index of array to be updated
 
val -. The new value to be updated
 
*/
static void updateValueUtil(int si, int ss, int se,
                            int idx, int val)
{
     
    // Leaf node
    if (ss == se)
    {
        tree[si] = tree[si] - arr[idx] + val;
        arr[idx] = val;
    }
    else
    {
        int mid = getMid(ss, se);
         
        // If idx is in the left child,
        // recurse on the left child
        if (ss <= idx && idx <= mid)
            updateValueUtil(2 * si + 1, ss,
                            mid, idx, val);
 
        // If idx is in the right child,
        // recurse on the right child
        else
            updateValueUtil(2 * si + 2, mid + 1,
                            se, idx, val);
 
        // Internal node will have the sum
        // of both of its children
        tree[si] = tree[2 * si + 1] +
                   tree[2 * si + 2];
    }
}
 
/* A recursive function to get the number
of Powerful numbers in a given
range of array indexes
 
si -. Index of current node in the segment tree.
    Initially 0 is passed as root is always
    at index 0.
ss & se -. Starting and ending indexes of the
            segment represented by current node,
            i.e., st[index]
l & r -. Starting and ending indexes of
        query range
 
*/
static int queryPowerfulUtil(int si, int ss,
                             int se, int l, int r)
{
     
    // If segment of this node is
    // outside the given range
    if (r < ss || se < l)
    {
        return 0;
    }
     
    // If segment of this node is a part
    // of given range, then return the
    // number of composites
    // in the segment
    if (l <= ss && se <= r)
    {
        return tree[si];
    }
 
    // If a part of this segment
    // overlaps with the given range
    int mid = getMid(ss, se);
    int p1 = queryPowerfulUtil(2 * si + 1,
                               ss, mid, l,
                               r);
    int p2 = queryPowerfulUtil(2 * si + 2,
                                  mid + 1,
                                 se, l, r);
    return (p1 + p2);
}
 
static void queryPowerful(int n, int l, int r)
{
    Console.WriteLine("Number of Powerful numbers " +
                      "between " + l +" to "+r+" = "+
                      queryPowerfulUtil(0, 0, n - 1,
                                        l, r));
}
 
static void updateValue(int n, int ind, int val)
{
     
    // If val is a Powerful number
    // we will update 1 in tree
    if (powerful[val])
        updateValueUtil(0, 0, n - 1,
                        ind, 1);
    else
        updateValueUtil(0, 0, n - 1,
                        ind, 0);
}
 
static void precomputePowerful()
{
    
    for(int i = 0; i <= MAX; i++)
        powerful[i] = false;
     
    // Computing all Powerful
    // numbers till MAX
    for(int i = 1; i <= MAX; i++)
    {
         
        // If the number is
        // Powerful make
        // powerful[i] = true
        if (isPowerful(i))
            powerful[i] = true;
    }
}
 
// Driver Code
public static void Main(String[] args)
{
     
    // Precompute all the powerful
    // numbers till MAX
    precomputePowerful();
 
    // Input array
    int []input = { 4, 5, 18, 27, 40, 144 };
     
    // Size of Input array
    int n = input.Length;
 
    // Build the array.
    BuildArray(input, n);
     
    // Build segment tree from
    // given array
    constructSTUtil(0, 0, n - 1);
 
    // Query 1: Query(L = 0, R = 3)
    int l = 0, r = 3;
    queryPowerful(n, l, r);
 
    // Query 2: Update(i = 1, x = 9),
    // i.e Update input[i] to x
    int i = 1;
    int val = 9;
    updateValue(n, i, val);
 
    // Query 3: Query(L = 0, R = 3)
    queryPowerful(n, l, r);
}
}
 
// This code is contributed by Rohit_ranjan

Javascript




<script>
 
    // JavaScript program to find the number
    // of Powerful numbers in subarray
    // using segment tree
     
    let MAX = 100000;
  
    // Size of segment tree = 2^{log(MAX)+1}
    let tree = new Array(3 * MAX);
    let arr = new Array(MAX);
    let powerful = new Array(MAX + 1);
 
    // Function to check if the
    // number is powerful
    function isPowerful(n)
    {
 
        // First divide the number
        // repeatedly by 2
        while (n % 2 == 0)
        {
            let power = 0;
            while (n % 2 == 0)
            {
                n = parseInt(n / 2, 10);
                power++;
            }
 
            // If only 2^1 divides
            // n (not higher powers),
            // then return false
            if (power == 1)
                return false;
        }
 
        // If n is not a power of 2 then
        // this loop will execute
        // repeat above process
        for(let factor = 3;
                factor <= Math.sqrt(n);
                factor += 2)
        {
 
            // Find highest power of
            // "factor" that divides n
            let power = 0;
            while (n % factor == 0)
            {
                n = parseInt(n / factor, 10);
                power++;
            }
 
            // If only factor^1 divides n
            // (not higher powers),
            // then return false
            if (power == 1)
                return false;
        }
 
        // n must be 1 now if it is not
        // a prime numenr. Since prime
        // numbers are not powerful,
        // we return false if n is not 1.
        return (n == 1);
    }
 
    // Function to build the array
    function BuildArray(input, n)
    {
        for(let i = 0; i < n; i++)
        {
 
            // Check if input[i] is
            // a Powerful number or not
            if (powerful[input[i]])
                arr[i] = 1;
 
            else
                arr[i] = 0;
        }
        return;
    }
 
    // A utility function to get the middle
    // index from corner indexes.
    function getMid(s, e)
    {
        return s + parseInt((e - s) / 2, 10);
    }
 
    /* A recursive function that constructs
    Segment Tree for array[ss..se].
 
    si -. Index of current node in the
        segment tree. Initially 0 is
        passed as root is always
        at index 0.
    ss & se -. Starting and ending indexes
                of the segment represented by
                current node, i.e., st[index]
    */
    function constructSTUtil(si, ss, se)
    {
        if (ss == se)
        {
 
            // If there is one element
            // in array
            tree[si] = arr[ss];
            return;
        }
 
        // If there are more than one elements,
        // then recur for left and right subtrees
        // and store the sum of the two
        // values in this node
        else
        {
            let mid = getMid(ss, se);
 
            constructSTUtil(2 * si + 1,
                            ss, mid);
 
            constructSTUtil(2 * si + 2,
                            mid + 1, se);
 
            tree[si] = tree[2 * si + 1] +
                       tree[2 * si + 2];
        }
    }
 
    /* A recursive function to update the
    nodes which have the given index
    in their range.
 
    si -. Index of current node in the segment tree.
        Initially 0 is passed as root is always
        at index 0.
    ss & se -. Starting and ending indexes of the
                segment represented by current node,
                i.e., st[index]
 
    ind -. Index of array to be updated
 
    val -. The new value to be updated
 
    */
    function updateValueUtil(si, ss, se, idx, val)
    {
 
        // Leaf node
        if (ss == se)
        {
            tree[si] = tree[si] - arr[idx] + val;
            arr[idx] = val;
        }
        else
        {
            let mid = getMid(ss, se);
 
            // If idx is in the left child,
            // recurse on the left child
            if (ss <= idx && idx <= mid)
                updateValueUtil(2 * si + 1, ss,
                                mid, idx, val);
 
            // If idx is in the right child,
            // recurse on the right child
            else
                updateValueUtil(2 * si + 2, mid + 1,
                                se, idx, val);
 
            // Internal node will have the sum
            // of both of its children
            tree[si] = tree[2 * si + 1] +
                       tree[2 * si + 2];
        }
    }
 
    /* A recursive function to get the number
    of Powerful numbers in a given
    range of array indexes
 
    si -. Index of current node in the segment tree.
        Initially 0 is passed as root is always
        at index 0.
    ss & se -. Starting and ending indexes of the
                segment represented by current node,
                i.e., st[index]
    l & r -. Starting and ending indexes of
            query range
 
    */
    function queryPowerfulUtil(si, ss, se, l, r)
    {
 
        // If segment of this node is
        // outside the given range
        if (r < ss || se < l)
        {
            return 0;
        }
 
        // If segment of this node is a part
        // of given range, then return the
        // number of composites
        // in the segment
        if (l <= ss && se <= r)
        {
            return tree[si];
        }
 
        // If a part of this segment
        // overlaps with the given range
        let mid = getMid(ss, se);
        let p1 = queryPowerfulUtil(2 * si + 1,
                                   ss, mid, l,
                                   r);
        let p2 = queryPowerfulUtil(2 * si + 2,
                                      mid + 1,
                                     se, l, r);
        return (p1 + p2);
    }
 
    function queryPowerful(n, l, r)
    {
        document.write("Number of Powerful numbers " +
                          "between " + l +" to "+r+" = "+
                          queryPowerfulUtil(0, 0, n - 1,
                                            l, r) + "</br>");
    }
 
    function updateValue(n, ind, val)
    {
 
        // If val is a Powerful number
        // we will update 1 in tree
        if (powerful[val])
            updateValueUtil(0, 0, n - 1,
                            ind, 1);
        else
            updateValueUtil(0, 0, n - 1,
                            ind, 0);
    }
 
    function precomputePowerful()
    {
 
        for(let i = 0; i <= MAX; i++)
            powerful[i] = false;
 
        // Computing all Powerful
        // numbers till MAX
        for(let i = 1; i <= MAX; i++)
        {
 
            // If the number is
            // Powerful make
            // powerful[i] = true
            if (isPowerful(i))
                powerful[i] = true;
        }
    }
     
    // Precompute all the powerful
    // numbers till MAX
    precomputePowerful();
  
    // Input array
    let input = [ 4, 5, 18, 27, 40, 144 ];
      
    // Size of Input array
    let n = input.length;
  
    // Build the array.
    BuildArray(input, n);
      
    // Build segment tree from
    // given array
    constructSTUtil(0, 0, n - 1);
  
    // Query 1: Query(L = 0, R = 3)
    let l = 0, r = 3;
    queryPowerful(n, l, r);
  
    // Query 2: Update(i = 1, x = 9),
    // i.e Update input[i] to x
    let i = 1;
    let val = 9;
    updateValue(n, i, val);
  
    // Query 3: Query(L = 0, R = 3)
    queryPowerful(n, l, r);
 
</script>
Output: 
Number of Powerful numbers between 0 to 3 = 2
Number of Powerful numbers between 0 to 3 = 3

 

Time Complexity: O(logN) per query
 




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