🐣 문제

링크 : https://www.acmicpc.net/problem/1157

🐥 코드

#include <iostream>
#include <string>


using namespace std;

int main() {
  string s = "";
  cin >> s;

  for(char& ch : s)
    ch = toupper(ch);

  int arr[26] = {0, };

  for(char& ch : s){
    arr[ch - 'A'] ++;
  }

  int max = 0;
  int index = 0;
  for(int i = 0; i < 26; i++){
   if(arr[i] > max){
     max = arr[i]; 
     index = i;
    }
  }

  int count = 0;
  for(int i = 0; i < 26; i++){
    if(arr[i] == max)
      count ++;
  }

  if (count == 1)
    cout << (char)(index + 'A') << endl;
  else
    cout << "?" << endl;
  return 0;
}