text: #include <iostream>
  #include <cstdio>
  #include <string.h>
  using namespace std;
  int main() {
      int n, cnt = 0;
      char a[50], b[50];
      double temp, sum = 0.0;
      cin >> n;
      for(int i = 0; i < n; i++) {
          scanf("%s", a);
          sscanf(a, "%lf", &temp);
          sprintf(b, "%.2f",temp);
          int flag = 0;
          for(int j = 0; j < strlen(a); j++)
              if(a[j] != b[j]) flag = 1;
          if(flag || temp < -1000 || temp > 1000) {
              printf("ERROR: %s is not a legal number\n", a);
              continue;
          } else {
              sum += temp;
              cnt++;
          }
      }
      if(cnt == 1)
          printf("The average of 1 number is %.2f", sum);
      else if(cnt > 1)
          printf("The average of %d numbers is %.2f", cnt, sum / cnt);
      else
          printf("The average of 0 numbers is Undefined");
      return 0;
  }