C++ Program to Check if all array elements can be converted to pronic numbers by rotating digits

Given an array arr[] of size N, the task is to check if it is possible to convert all of the array elements to a pronic number by rotating the digits of array elements any number of times.

Examples:

Input: {321, 402, 246, 299}
Output: True
Explanation:
arr[0] ? Right rotation once modifies arr[0] to 132 (= 11 × 12).
arr[1] ? Right rotation once modifies arr[0] to 240 (= 15 × 16).
arr[2] ? Right rotation twice modifies arr[2] to 462 (= 21 × 22).
arr[3] ? Right rotation twice modifies arr[3] to 992 (= 31 × 32).
Input: {433, 653, 402, 186}
Output: False

Approach: Follow the steps below to solve the problem:

Traverse the array and check for each array element, whether it is possible to convert it to a pronic number.
For each array element, apply all the possible rotations and check after each rotation, whether the generated number is pronic or not.
If it is not possible to convert any array element to a pronic number, print “False”.
Otherwise, print “True”.

Below is the implementation of the above approach:

C++

// C++ program for the above approach
#include <bits/stdc++.h>
using namespace std;
  
// function to check Pronic Number
bool isPronic(int x)
{
    for (int i = 0; i < (int)(sqrt(x)) + 1; i++) 
    {
  
        // Checking Pronic Number
        // by multiplying consecutive
        // numbers
        if (x == i * (i + 1)) 
        {
            return true;
        }
    }
    return false;
}
  
// Function to check if any permutation
// of val is a pronic number or not
bool checkRot(int val)
{
  
    string temp = to_string(val);
    for (int i = 0; i < temp.length(); i++) 
    {
        if (isPronic(stoi(temp)) == true)
        {
            return true;
        }
        temp = temp.substr(1, temp.size() - 1) + temp[0];
    }
    return false;
}
  
// Function to check if all array
// elements can be converted to
// a pronic number or not
bool check(int arr[], int N)
{
  
    // Traverse the array
    for (int i = 0; i < N; i++) 
    {
  
        // If current element
        // cannot be converted
        // to a pronic number
        if (checkRot(arr[i]) == false) 
        {
            return false;
        }
    }
    return true;
}
  
// Driven Program
int main()
{
    
    // Given array
    int arr[] = { 321, 402, 246, 299 };
    int N = sizeof(arr) / sizeof(arr[0]);
  
    // function call
    cout << (check(arr, N) ? "True" : "False");
  
    return 0;
}
  
// This code is contributed by Kingash.