题解 | 游游的字符重排

#include<bits/stdc++.h>
#define endl '\n'
using namespace std;

int main() {
    string s;cin >> s;
    int len = s.length();
    int ans = 0;
    sort(s.begin(),s.end());
    do {
        for(int i = 1;i<len;i++) {
            if(s[i] == s[i-1]) break;
            if(i == len-1) ans++;
        }
    }while(next_permutation(s.begin(),s.end()));
    cout << ans << endl;
}

暴力大法大好哇

(`3´)