링크 : https://school.programmers.co.kr/learn/courses/30/lessons/12916
#include <string>
#include <iostream>
using namespace std;
bool solution(string s)
{
bool answer = true;
int num1 = 0, num2 =0;
for(int i = 0; i < s.length(); i++){
if(s[i] == 'p' || s[i] == 'P')
num1 ++;
else if(s[i] == 'y' || s[i] == 'Y')
num2 ++;
}
if (num1 != num2)
answer = false;
return answer;
}