codeforces 1114B

切割N個數成K快每塊取M個最大的數，求最大值

排序标記M*K個最大值，之後每M個輸出一個下标

#include <cstdio>
    #include <bits/stdc++.h>
    using namespace std;
    const int MAX_N = 2e5 +100;
    const int MAX_M = 10010;
    typedef long long LL;
    #define sci(num) scanf("%d",&num)
    int N,M,K;
    struct as {
        int num,loc;
    } a[MAX_N];
    bool mark[MAX_N];
    bool cmp1(const as& a1,const as& a2) {
        if (a1.num != a2.num) return a1.num > a2.num;
        return a1.loc < a2.loc;
    }
    int main() {
        ios::sync_with_stdio(false); cin.tie(0);
        cin >> N >> M >> K;
        for (int i = 0;i < N;i++) {
            a[i].loc = i;
            cin >> a[i].num;
        }
        sort(a,a + N,cmp1);
        LL sum = 0;
        for (int i = 0;i < M * K;i++) {
            sum += a[i].num;
            mark[a[i].loc] = true;
        }
        int cnt = 0;
        int wch = 1;
        cout << sum << endl;
        bool flag = true;
        for (int i = 0;i < N && wch < K;i++) {
            if (mark[i]) cnt++;
            if (cnt == M) {
                cnt = 0;
                wch++;
                if (flag) {
                    cout << i + 1;
                    flag = false;
                } else {
                    cout << " " << i + 1;
                }
            }
        }
        cout << endl;
    
        return 0;
    }