Find the length of largest subarray in which all elements are Autobiographical Numbers

Given an array arr[] of integers, our task is to find the length of the largest subarray such that all the elements of the sub-array are Autobiographical Number.

An Autobiographical Number is a number such that the first digit of it counts how many zeroes are there in it, the second digit counts how many ones are there and so on. 
For example, 21200 has 2 zero, 1 one, 2 two and 0 three and 0 four. 

Examples:

Input: arr[]={21200, 1, 1303, 1210, 2020} 
Output: 2 
Explanation:
Maximum length of subarray with all numbers as Autobiographical Number is {1210, 2020}.
Input: arr[]={100, 200, 300, 400, 1200, 500} 
Output: 0 
Explanation:
None of them are Autobiographical Number. 

Approach:
To solve the problem mentioned above we have to follow the steps given below:

• Traverse the array from index 0 and initialize a max_length and current_length variable with 0.
• If the current element is an autobiographical number then increment current_length variable and continue, otherwise set current_length to 0.
• At each step, assign max_length as max_length = max(current_length, max_length). The final value of max_length will store the required result.

Below is the implementation of the above approach: 

C++

// C++ program to find the length of the
// largest subarray whose every element is an
// Autobiographical Number

#include <bits/stdc++.h>
using namespace std;

// function to check number is autobiographical
bool isAutoBiographyNum(int number)
{

    int count = 0, position, size, digit;
    string NUM;

    // Convert integer to string
    NUM = to_string(number);
    size = NUM.length();

    // Iterate for every digit to check
    // for their total count
    for (int i = 0; i < size; i++) {
        position = NUM[i] - '0';
        count = 0;

        // Check occurrence of every number
        // and count them
        for (int j = 0; j < size; j++) {
            digit = NUM[j] - '0';
            if (digit == i)
                count++;
        }

        // Check if any position mismatches with
        // total count them return with false
        // else continue with loop
        if (position != count)
            return false;
    }

    return true;
}

// Function to return the length of the
// largest subarray whose every
// element is a Autobiographical number
int checkArray(int arr[], int n)
{

    int current_length = 0;
    int max_length = 0;

    // Utility function which checks every element
    // of array for Autobiographical number
    for (int i = 0; i < n; i++) {

        // Check if element arr[i] is an
        // Autobiographical number
        if (isAutoBiographyNum(arr[i]))
            // Increment the current length
            current_length++;

        else
            current_length = 0;

        // Update max_length value
        max_length = max(max_length, current_length);
    }

    // Return the final result
    return max_length;
}

// Driver code
int main()
{
    int arr[] = { 21200, 1, 1303, 1210, 2020 };

    int n = sizeof(arr) / sizeof(arr[0]);

    cout << checkArray(arr, n) << "\n";
    return 0;
}

Java

// Java program to find the length of the
// largest subarray whose every element is
// an autobiographical number
class GFG {

// Function to check number is autobiographical
static boolean isAutoBiographyNum(int number)
{

    int count = 0, position, size, digit;
    String NUM;

    // Convert integer to string
    NUM = Integer.toString(number);
    size = NUM.length();

    // Iterate for every digit to check
    // for their total count
    for(int i = 0; i < size; i++)
    {
       position = NUM.charAt(i) - '0';
       count = 0;

       // Check occurrence of every number
       // and count them
       for(int j = 0; j < size; j++)
       {
          digit = NUM.charAt(j) - '0';
          if (digit == i)
              count++;
       }

       // Check if any position mismatches with
       // total count them return with false
       // else continue with loop
       if (position != count)
           return false;
    }

    return true;
}

// Function to return the length of the
// largest subarray whose every
// element is a Autobiographical number
static int checkArray(int arr[], int n)
{
    int current_length = 0;
    int max_length = 0;

    // Utility function which checks every element
    // of array for autobiographical number
    for(int i = 0; i < n; i++)
    {

       // Check if element arr[i] is an
       // autobiographical number
       if (isAutoBiographyNum(arr[i]) == true)
       {

           // Increment the current length
           current_length++;
       }
       else
       {
           current_length = 0;
       }

       // Update max_length value
       max_length = Math.max(max_length, current_length);
    }

    // Return the final result
    return max_length;
}

// Driver code
public static void main (String[] args)
{
    int arr[] = { 21200, 1, 1303, 1210, 2020 };
    int n = arr.length;

    System.out.println(checkArray(arr, n));
}
}

// This code is contributed by AnkitRai01

Python3

# Python3 program to find the length of the
# largest subarray whose every element is an
# autobiographical number

# Function to check number is autobiographical
def isAutoBiographyNum(number):

    count = 0;

    # Convert integer to string
    NUM = str(number);
    size = len(NUM);

    # Iterate for every digit to check
    # for their total count
    for i in range(size):
        position = ord(NUM[i]) - ord('0');
        count = 0;

        # Check occurrence of every number
        # and count them
        for j in range(size):

            digit = ord(NUM[j]) - ord('0');
            if (digit == i):
                count += 1;

        # Check if any position mismatches with
        # total count them return with false
        # else continue with loop
        if (position != count):
            return False;

    return True;

# Function to return the length of the
# largest subarray whose every
# element is a autobiographical number
def checkArray(arr, n):

    current_length = 0;
    max_length = 0;

    # Utility function which checks every element
    # of array for autobiographical number
    for i in range(n):

        # Check if element arr[i] is an
        # autobiographical number
        if (isAutoBiographyNum(arr[i])):

            # Increment the current length
            current_length += 1;
        else:
            current_length = 0;

        # Update max_length value
        max_length = max(max_length,
                         current_length);

    # Return the final result
    return max_length;

# Driver code
if __name__ == "__main__":

    arr = [ 21200, 1, 1303, 1210, 2020 ];
    n = len(arr);

    print(checkArray(arr, n));

# This code is contributed by AnkitRai01

C#

// C# program to find the length of the
// largest subarray whose every element
// is an autobiographical number
using System;

class GFG {

// Function to check number is autobiographical
static bool isAutoBiographyNum(int number)
{
    int count = 0, position, size, digit;
    string NUM;

    // Convert integer to string
    NUM = number.ToString();
    size = NUM.Length;

    // Iterate for every digit to check
    // for their total count
    for(int i = 0; i < size; i++)
    {
       position = NUM[i] - '0';
       count = 0;

       // Check occurrence of every number
       // and count them
       for(int j = 0; j < size; j++)
       {
          digit = NUM[j] - '0';
          if (digit == i)
              count++;
       }

       // Check if any position mismatches
       // with total count them return with
       // false else continue with loop
       if (position != count)
           return false;
    }
    return true;
}

// Function to return the length of the
// largest subarray whose every element
// is a autobiographical number
static int checkArray(int []arr, int n)
{
    int current_length = 0;
    int max_length = 0;

    // Utility function which checks every element
    // of array for autobiographical number
    for(int i = 0; i < n; i++)
    {

       // Check if element arr[i] is an
       // autobiographical number
       if (isAutoBiographyNum(arr[i]) == true)
       {

           // Increment the current length
           current_length++;
       }
       else
       {
           current_length = 0;
       }

       // Update max_length value
       max_length = Math.Max(max_length,
                             current_length);
    }

    // Return the final result
    return max_length;
}

// Driver code
public static void Main (string[] args)
{
    int []arr = { 21200, 1, 1303, 1210, 2020 };
    int n = arr.Length;

    Console.WriteLine(checkArray(arr, n));
}
}

// This code is contributed by AnkitRai01

Javascript

<script>

    // Javascript program to find the length of the
    // largest subarray whose every element is an
    // Autobiographical Number

    // function to check number is autobiographical
    function isAutoBiographyNum(number)
    {

        let count = 0, position, size, digit;
        let NUM;

        // Convert integer to string
        NUM = number.toString();
        size = NUM.length;

        // Iterate for every digit to check
        // for their total count
        for (let i = 0; i < size; i++) {
            position = NUM[i].charCodeAt() - '0'.charCodeAt();
            count = 0;

            // Check occurrence of every number
            // and count them
            for (let j = 0; j < size; j++) {
                digit = NUM[j].charCodeAt() - '0'.charCodeAt();
                if (digit == i)
                    count++;
            }

            // Check if any position mismatches with
            // total count them return with false
            // else continue with loop
            if (position != count)
                return false;
        }

        return true;
    }

    // Function to return the length of the
    // largest subarray whose every
    // element is a Autobiographical number
    function checkArray(arr, n)
    {

        let current_length = 0;
        let max_length = 0;

        // Utility function which checks every element
        // of array for Autobiographical number
        for (let i = 0; i < n; i++) {

            // Check if element arr[i] is an
            // Autobiographical number
            if (isAutoBiographyNum(arr[i]))
                // Increment the current length
                current_length++;

            else
                current_length = 0;

            // Update max_length value
            max_length = Math.max(max_length, current_length);
        }

        // Return the final result
        return max_length;
    }

    let arr = [ 21200, 1, 1303, 1210, 2020 ];

    let n = arr.length;

    document.write(checkArray(arr, n));


</script>

Output:

2

Time Complexity: O(n * log n)

Auxiliary Space: O(1)