不知道为啥60分，求解，C++

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

  	int main() {
	
      string str;
      int n = 0;
      cin >> str;
      n = str.length();
      int arr[100] = { 0 };

      int u,b;
      b = 0;
      u = 0;
      for (int i = 0; i < n; i++) {
          b = 0;
          for (int l = 0; l < n; l++) {
              if (str[i] == str[l]) {
                  b++;
                  arr[u] = b;
              }
          }
          u++;
      }
      int x = 0;
      int y = 100;
      for (int i = 0; i < u; i++) {
          if (x < arr[i]) {
              x = arr[i];
          }		
          if (y > arr[i]) {
              y = arr[i];
          }	
      }

      int d = 0;
      for (int i = 1; i < 100; i++) {
          if ((x-y) % i == 0)
              d++;
      }
      if (d == 2) {
          cout << "Lucky Word" << endl;
          cout << x-y;
      }
      else {
          cout << "No Answer" << endl;
          cout << x-y;
      }
      return 0;
  	}