Submission #642423

#	Time	Username	Problem	Language	Result	Execution time	Memory
642423		burak_ozzkan	Knapsack (NOI18_knapsack)	C++14	0 / 100	113 ms	262144 KiB

knapsack

#include <bits/stdc++.h>
#define nl '\n'
#define int long long
using namespace std;

/*
f(i, j, k) = max value where i can use k item from ith type, using first i items, sack size = j

f(i, j, k){
    max(v[i].value+f(i, j-v[i].weight, k-1), f(i-1, j, k))
}

15 5
4 12 1
2 1 1
10 4 1
1 1 1
2 2 1

20 3
5000 15 1
100 1 3
50 1 4
*/

struct item{
    int value;
    int weight;
    int piece;
};

void solve(){
    int s, n;
    cin >> s >> n;

    vector<item> v(n);
    int max_k = -1;
    for(int i = 0; i < n; i++){
        item tmp;
        cin >> tmp.value >> tmp.weight >> tmp.piece;
        v[i] = tmp;
        max_k = max(max_k, tmp.piece);
    }

    vector< vector< vector<int> > > dp(n+10, vector< vector<int> >(s+10, vector<int>(max_k+10, -1)));
    function<int(int, int, int)> f = [&](int i, int j, int k){
        if(i < 0 || j < 0 || k < 0) return 0LL;
        if(dp[i][j][k] != -1) return dp[i][j][k];
        if(k == 0 && i > 0) return dp[i][j][k] = f(i-1, j, v[i-1].piece);

        int t1 = 0;
        if(j-v[i].weight >= 0) t1 = v[i].value + f(i, j-v[i].weight, k-1);

        int t2 = 0;
        if(i-1 >= 0) t2 = f(i-1, j, v[i-1].piece);

        return dp[i][j][k] = max(t1, t2);
    };

    cout << f(n-1, s, v[n-1].piece) << nl;;
}

int32_t main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    int t = 1; /*cin >> t;*/ while(t--) solve();
}

• Subtask 1: 0 / 12
• Subtask 2: 0 / 17
• Subtask 3: 0 / 20
• Subtask 4: 0 / 24
• Subtask 5: 0 / 27