题解 | 排序危机

#include <iostream>
using namespace std;

int main() {
    int n;
    string s,s_little,s_number,s_big;
    int  l =0,num=0,b = 0;
    cin >> n;
    cin >> s;
    for(int i = 0;i<n;++i){
        //数字
      if(s[i]>=48 && s[i]<=57){
        s_number+=s[i];
        
      }
      //大写字母
      else if(s[i]>=65 && s[i]<=90){
        s_big+=s[i];
        
      }
      //小写字母
       else if(s[i]>=97 && s[i]<=122){
        s_little+=s[i];
        
      }
    }
    cout << s_little <<s_number <<s_big;
}