Submission #863422

#	Time	Username	Problem	Language	Result	Execution time	Memory
863422		tienbinh	Knapsack (NOI18_knapsack)	C++17	100 / 100	62 ms	4948 KiB

knapsack

#include <bits/stdc++.h>
using namespace std;
int s , n;
const int N = 1e5 + 7;
int w[N] , v[N] , k[N];
vector<pair<int ,int>> adj[2007];
long long dp[2][2007];
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);   
    cin >> s >> n;
    for(int i = 1 ; i <= n ; i++){
        cin >> v[i] >> w[i] >> k[i];
        adj[w[i]].emplace_back(v[i] , k[i]);
    }
    for(int i = 1; i <= 2000 ; i ++) sort(adj[i].rbegin() , adj[i].rend());
    n = 0;
    for(int i = 1 ; i <= 2000 ; i++){
        int lim = s / i;
        for(int j = 0, h = 0; j < lim; j++) {
            if (h == (int)adj[i].size()) break;
            w[++n] = i;
            v[n] = adj[i][h].first;
            adj[i][h].second--;
            if (!adj[i][h].second) h++;
        }
    }
    memset(dp , 0xef , sizeof dp);
    dp[0][0] = 0;
    for(int i = 1 ; i <= n ; i++){
        for(int val = s ; val >= 0 ; val--) {
            dp[i & 1][val] = dp[~i & 1][val];
            if (val >= w[i])
                dp[i & 1][val] = max(dp[i & 1][val], dp[~i & 1][val - w[i]] + v[i]);
        }
    }
    long long ans = numeric_limits<long long>::min();
    for (int i = 0; i <= s; i++)
        ans = max(ans, dp[n & 1][i]);
    cout << ans << '\n';
}

• Subtask 1: 12 / 12
• Subtask 2: 17 / 17
• Subtask 3: 20 / 20
• Subtask 4: 24 / 24
• Subtask 5: 27 / 27