我与豆包一起做的题解

#include<bits/stdc++.h>
using namespace std;
const int MAXM = 100005;
const int INF = 0x3f3f3f3f;

int dp[MAXM];
int A[25];
int s[MAXM];

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    for(int i = 1; i <= n; i++){
        cin >> A[i];
    }
    int m;
    string str;
    cin >> m >> str;

    s[m] = 0;
    for(int i = m - 3; i >= 0; i--){
        if(str[i] == 'a' && str[i+1] == 'b' && str[i+2] == 'c'){
            s[i] = s[i + 3] + 1;
        }else{
            s[i] = 0;
        }
    }

    for(int i = 0; i <= m; i++) dp[i] = -INF;
    dp[0] = 0;

    for(int i = 0; i <= m; i++){
        if(dp[i] == -INF) continue;

        if(i + 1 <= m){
            dp[i+1] = max(dp[i+1], dp[i]);
        }

        int t = s[i];
        int maxk = min(t, n);
        for(int k = 1; k <= maxk; k++){
            int nxt = i + 3 * k;
            if(nxt > m) continue;
            dp[nxt] = max(dp[nxt], dp[i] + A[k]);
        }
    }
    cout << dp[m] << endl;
    return 0;
}