zoj 3908 Number Game(STL)

题目连接：zoj 3908 Number Game

代码

#include <cstdio>#include <cstring>#include <set>#include <vector>#include <algorithm>using namespace std;typedef long long ll;typedef multiset<int>::iterator iter;int N, M, K;multiset<int> G;vector<int> S;void init () {    G.clear();    scanf("%d%d%d", &N, &M, &K);    int x;    for (int i = 0; i < N; i++) {        scanf("%d", &x);        if (x == 0) continue;        G.insert(x);    }}ll solve () {    S.clear();    while (!G.empty()) {        iter it = G.end(); it--;        int u = *it;        G.erase(it);        it = G.upper_bound(K-u);        if (it == G.begin()) continue;        it--;        int v = *it;        G.erase(it);        S.push_back(u * v);    }    ll ret = 0;    sort(S.begin(), S.end());    int n = S.size();    for (int i = 1; i <= M && i <= n; i++) {        ret += S[n-i];    }    return ret;}int main () {    int cas;    scanf("%d", &cas);    while (cas--) {        init();        printf("%lld\n", solve());    }    return 0;}