状压DP

#include<bits/stdc++.h>
using namespace std;

typedef long long LL;
LL n, m, k, a[20], c[20][20], dp[1 << 20][20];

LL solve(int cnt, int state, int tail) {
    if(cnt == m) return 0;
    LL &ret = dp[state][tail];
    if(ret != -1) return ret;
    for(int i = 1; i <= n; i++)
        if(!(state & (1 << i))) ret = max(ret, solve(cnt + 1, state | (1 << i), i) + c[tail][i] + a[i]);
    return ret;
}

int main() {
    memset(dp, -1, sizeof(dp));
    cin >> n >> m >> k;
    for(int i = 1; i <= n; i++) scanf("%d", a + i);
    while(k--) {
        int x, y, z;
        scanf("%d%d%d", &x, &y, &z);
        c[x][y] = z;
    }
    cout << solve(0, 0, 0) << endl;
}