Submission #848199

#	Time	Username	Problem	Language	Result	Execution time	Memory
848199		vjudge1	Knapsack (NOI18_knapsack)	C++17	12 / 100	0 ms	348 KiB

knapsack

#include <bits/stdc++.h>
#define int long long
#define pii pair<int, int>
#define pb push_back
#define gcd __gcd
#define endl "\n"
#define task "hihi"
using namespace std;
const int N = 2000 + 5, MOD = 1e9 + 7, INF = 1e18 + 5; 
int s, n, dp[N];
vector<array<int, 3>> items; 
vector<pii> need[N];
vector<pii> fin;
signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    //freopen(task".inp", "r", stdin);
    //freopen(task".out", "w", stdout);
    cin >> s >> n;
    for(int i = 1; i <= n; i++){
        int v, w, k; cin >> v >> w >> k;
        k = min(k, s / w);
        need[w].pb({v, k});
    }
    for(int i = 1; i <= s; i++){
        sort(need[i].begin(), need[i].end());
        int ntt = s / i;
        for(pii x : need[i]){
            int taken = min(ntt, x.second);
            items.pb({i, x.first, taken});
            ntt -= x.second;
            if(ntt <= 0) break;
        }   
    }
    for(array<int, 3> x : items){
        int cnt = 1, needed = x[2];
        while(cnt <= needed){
            fin.pb({cnt * x[0], cnt * x[1]});
            needed -= cnt, cnt *= 2;
        }
        if(needed){
            fin.pb({x[0] * needed, x[1] * needed});
        }
    }
    for(int i = 1; i <= s; i++) dp[i] = -INF;
    int ans = 0;
    for(int i = 0; i < fin.size(); i++){
        for(int j = s; j >= fin[i].first; j--){
            dp[j] = max(dp[j], dp[j - fin[i].first] + fin[i].second);
            ans = max(ans, dp[j]);
        }
    }
    cout << ans << endl;
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:47:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |     for(int i = 0; i < fin.size(); i++){
      |                    ~~^~~~~~~~~~~~

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