Find sum of a number and its maximum prime factor in C++

Suppose we have a positive number n, and we have to find the sum of N and its maximum prime factor. So when the number is 26, then maximum prime factor is 13, so sum will be 26 + 13 = 39.

Approach is straight forward. Simply find the max prime factor, and calculate the sum and return.

Example

 Live Demo

#include<iostream> #include<cmath> using namespace std; int maxPrimeFact(int n){    int num = n;    int maxPrime = -1;    while (n % 2 == 0) {       maxPrime = 2;       n /= 2;    }    for (int i = 3; i <= sqrt(n); i += 2) {       while (n % i == 0) {          maxPrime = i;          n = n / i;       }    }    if (n > 2)    maxPrime = n;    return maxPrime; } int getRes(int n) {    int sum = maxPrimeFact(n) + n;    return sum; } int main() {    int n = 26;    cout << "Sum of " << n <<" and its max prime factor is: " << getRes(n); }

Output

Sum of 26 and its max prime factor is: 39