期中考抽獎

#include<iostream>
#include<algorithm>
#include<vector>
#include<random>
#include<functional>
using namespace std;
main() {
    string str = "FDforces Round #1 (Div. 1)";
    auto seed = hash<string>()(str);
    mt19937 mt(seed);
    vector<int> participant{4, 5, 7, 8, 9, 10};
    random_shuffle(participant.begin(), participant.end(), [&mt](int x) {
        uniform_int_distribution<> dis(0, x - 1);
        return dis(mt);
    });
    auto pick = bind(uniform_int_distribution<>(0, participant.size() - 1), mt);
    cout << participant[pick()] << endl;
    return 0;
}