Given an array of integers A. The task is to minimize the sum of the elements of the array using the following rule:
Choose two indices i and j and an arbitrary integer x, such that x is a divisor of A[i] and change them as following A[i] = A[i]/x and A[j] = A[j]*x.
Examples:
Input: A = { 1, 2, 3, 4, 5 }
Output: 14
Divide A[3] by 2 then
A[3] = 4/2 = 2,
Multiply A[0] by 2 then
A[0] = 1*2 = 2
Updated array A = { 2, 2, 3, 2, 5 }
Hence sum = 14
Input: A = { 2, 4, 2, 3, 7 }
Output: 18
Approach: If any number is divided by x then it is optimal to multiply the x with the smallest number present in the array.
The idea is to get the minimum of the array and find the divisors of the particular element and keep checking that by how much the sum is reduced.
Below is the implementation of the above approach:
// C++ implementation #include <bits/stdc++.h> using namespace std;
// Function to return the minimum sum void findMin( int arr[], int n)
{ int sum = 0;
for ( int i = 0; i < n; i++)
sum += arr[i];
// sort the array to find the
// minimum element
sort(arr, arr + n);
int min = arr[0];
int max = 0;
for ( int i = n - 1; i >= 1; i--) {
int num = arr[i];
int total = num + min;
int j;
// finding the number to
// divide
for (j = 2; j <= num; j++) {
if (num % j == 0) {
int d = j;
int now = (num / d)
+ (min * d);
// Checking to what
// instance the sum
// has decreased
int reduce = total - now;
// getting the max
// difference
if (reduce > max)
max = reduce;
}
}
}
cout << (sum - max);
} // Driver Code int main()
{ int arr[] = { 1, 2, 3, 4, 5 };
int n = sizeof (arr) / sizeof (arr[0]);
findMin(arr, n);
} |
// Java implementation of the above approach import java.util.*;
class GFG
{ // Function to return the minimum sum
static void findMin( int arr[], int n)
{
int sum = 0 ;
for ( int i = 0 ; i < n; i++)
sum += arr[i];
// sort the array to find the
// minimum element
Arrays.sort(arr);
int min = arr[ 0 ];
int max = 0 ;
for ( int i = n - 1 ; i >= 1 ; i--)
{
int num = arr[i];
int total = num + min;
int j;
// finding the number to
// divide
for (j = 2 ; j <= num; j++)
{
if (num % j == 0 )
{
int d = j;
int now = (num / d) +
(min * d);
// Checking to what
// instance the sum
// has decreased
int reduce = total - now;
// getting the max
// difference
if (reduce > max)
max = reduce;
}
}
}
System.out.println(sum - max);
}
// Driver Code
public static void main (String[] args)
{
int arr[] = { 1 , 2 , 3 , 4 , 5 };
int n = arr.length;
findMin(arr, n);
}
} // This code is contributed by AnkitRai01 |
# Function to return the minimum sum def findMin(arr, n):
sum = 0
for i in range ( 0 , n):
sum = sum + arr[i]
# sort the array to find the
# minimum element
arr.sort()
min = arr[ 0 ]
max = 0
for i in range (n - 1 , 0 , - 1 ):
num = arr[i]
total = num + min
# finding the number to
# divide
for j in range ( 2 , num + 1 ):
if (num % j = = 0 ):
d = j
now = (num / / d) + ( min * d)
# Checking to what
# instance the sum
# has decreased
reduce = total - now
# getting the max
# difference
if ( reduce > max ):
max = reduce
print ( sum - max )
# Driver Code arr = [ 1 , 2 , 3 , 4 , 5 ]
n = len (arr)
findMin(arr, n) # This code is contributed by Sanjit_Prasad |
// C# implementation of the above approach using System;
class GFG
{ // Function to return the minimum sum
static void findMin( int []arr, int n)
{
int sum = 0;
for ( int i = 0; i < n; i++)
sum += arr[i];
// sort the array to find the
// minimum element
Array.Sort(arr);
int min = arr[0];
int max = 0;
for ( int i = n - 1; i >= 1; i--)
{
int num = arr[i];
int total = num + min;
int j;
// finding the number to
// divide
for (j = 2; j <= num; j++)
{
if (num % j == 0)
{
int d = j;
int now = (num / d) +
(min * d);
// Checking to what
// instance the sum
// has decreased
int reduce = total - now;
// getting the max
// difference
if (reduce > max)
max = reduce;
}
}
}
Console.WriteLine(sum - max);
}
// Driver Code
public static void Main (String[] args)
{
int []arr = { 1, 2, 3, 4, 5 };
int n = arr.Length;
findMin(arr, n);
}
} // This code is contributed by PrinciRaj1992 |
<script> // Javascript implementation // Function to return the minimum sum function findMin(arr, n)
{ let sum = 0;
for (let i = 0; i < n; i++)
sum += arr[i];
// sort the array to find the
// minimum element
arr.sort();
let min = arr[0];
let max = 0;
for (let i = n - 1; i >= 1; i--) {
let num = arr[i];
let total = num + min;
let j;
// finding the number to
// divide
for (j = 2; j <= num; j++) {
if (num % j == 0) {
let d = j;
let now = parseInt(num / d)
+ (min * d);
// Checking to what
// instance the sum
// has decreased
let reduce = total - now;
// getting the max
// difference
if (reduce > max)
max = reduce;
}
}
}
document.write(sum - max);
} // Driver Code let arr = [ 1, 2, 3, 4, 5 ];
let n = arr.length;
findMin(arr, n);
</script> |
14
Time Complexity: O((N * logN) + (N * M)), where N is the size of the given array and M is the maximum element in the array.
Auxiliary Space: O(1), no extra space is required, so it is a constant.