Submission #1247871

#	Time	Username	Problem	Language	Result	Execution time	Memory
1247871		deeperxd	Knapsack (NOI18_knapsack)	C++20	100 / 100	88 ms	1980 KiB

knapsack

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

typedef long long ll;
#define MOD 998244353

#define SIZE 2001
ll dp[SIZE]{0};

float subprog(int n){
    float sum = 0;
    for(int i =1; i<= n; i++){
        sum += 1.0/i;
    }

    return sum;
}

int s;

void run_dp(int v, int w, int k){
for(int j = 0; j < k; j++)
        for(int c = s-w; c >= 0; c--){
            if (dp[c] == -1) continue;

            if (dp[c+w] == -1) dp[c+w] = dp[c] + v;
            else
            dp[c+w] = max(dp[c+w], dp[c]+v);
        }
}

int main(){
    int n;
    cin >> s >> n;

    for(int i = 0 ; i < SIZE; i++) dp[i] = -1;

    dp[0] = 0;

    map<int, vector<pair<int, int>>> mp; 

    for(int i = 0; i < n; i++){
        int v, w, k;
        cin >> v >> w >> k;

        mp[w].push_back({v, k});
    }

    for(auto &it : mp){
        auto vec = it.second;
        sort(vec.begin(), vec.end(), greater<pair<int, int>>());

        int sum_k = 0;
        int limit = SIZE / it.first;
        for(auto [v, k] : vec){
            if (sum_k + k >= limit){
                // the last one
                // to take should have biggest value such sum_k + to_take < SIZE
                int to_take = limit - sum_k;
                run_dp(v, it.first, to_take);
                break;
            }
            else{
                sum_k += k;
                run_dp(v, it.first, k);
            }
        }
    }

    ll mx = 0;
    for(int i = 0; i <= s; i++){
        if (dp[i] == -1)continue;
        mx = max(mx, dp[i]);
    }

    cout << mx << endl;
}

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