C++ Program - Find the largest prime factor of a number

  number = num

  Step 1: If num is divisible by 2, store
  largest prime factor as 2. keep on dividing
  num until it is not divisible by 2. After
  each division, update num as num/2.

  Step 2: At this point, num must be odd.
  Starting with 3 to square root of num, if
  divisible, divide and update num, and update
  largest prime factor.

  Step 3: if the modified num is greater than
  2, update the largest prime factor with num.

#include <iostream>
#include <cmath>
using namespace std;

long long MaxPrime(long long num) {
  long long CurrMaxPrime = -1;

  //If num is divisible by 2, store CurrMaxPrime
  //as 2. keep on dividing num until it is not 
  //divisible by 2. After each division, update 
  //num as num/2.
  if(num % 2 == 0) {
    CurrMaxPrime = 2;
    while(num % 2 == 0){
      num = num/2;
    }
  }
  
  //At this point, num must be odd. Starting with 
  //3 to square root of num , if divisible, divide 
  //and update num, and update CurrMaxPrime
  for(long long i = 3; i <= sqrt(num); i += 2) {
    while(num % i == 0) {
      CurrMaxPrime = i;
      num = num/i;
    }
  }

  //if the modified num is greater than 2, 
  //update the CurrMaxPrime with num 
  if (num > 2) 
    CurrMaxPrime = num;

  return CurrMaxPrime;
}

int main() {
  long long x, y, z;
  x = 42;
  y = 1092;
  z = 695467363456;

  cout<<"Largest prime factor of "<<x
      <<" is: "<<MaxPrime(x)<<"\n";
  cout<<"Largest prime factor of "<<y
      <<" is: "<<MaxPrime(y)<<"\n";
  cout<<"Largest prime factor of "<<z
      <<" is: "<<MaxPrime(z)<<"\n";
  return 0;
}