纯if，还挺简单的，つ﹏⊂

#include<bits/stdc++.h>
using namespace std;
int a[5];
string s;
int main(){
	cin>>a[1]>>a[2]>>a[3];
cin>>s;
sort(a+1,a+1+3);
if(s=="ABC")cout<<a[1]<<" "<<a[2]<<" "<<a[3];
if(s=="ACB")cout<<a[1]<<" "<<a[3]<<" "<<a[2];
if(s=="BAC")cout<<a[2]<<" "<<a[1]<<" "<<a[3];
if(s=="BCA")cout<<a[2]<<" "<<a[3]<<" "<<a[1];
if(s=="CAB")cout<<a[3]<<" "<<a[1]<<" "<<a[2];
if(s=="CBA")cout<<a[3]<<" "<<a[2]<<" "<<a[1];
return 0;
}

https://www.luogu.com.cn/team/88672

进去有很大帮助！！！