Submission #1086680

#	Time	Username	Problem	Language	Result	Execution time	Memory
1086680		ntmin	Knapsack (NOI18_knapsack)	C++14	100 / 100	79 ms	34300 KiB

knapsack

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, int> pli;
typedef pair<int, ll> pil;
#define all(x) x.begin(), x.end()
#define ON(a, b) (a >> b & 1)
template<typename T> bool maximise(T &a, T b){if(a < b){a = b; return 1;} return 0;}
template<typename T> bool minimise(T &a, T b){if(a > b){a = b; return 1;} return 0;}

const int N = 2001;
int s, n; 
vector<pair<ll, int>> weight[N];
ll dp[N][N];


int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    cin >> s >> n;

    for(int i = 1, v, w, k; i <= n; ++i){
        cin >> v >> w >> k;
        weight[w].push_back({v, k});
    }

    for(int i = 1; i <= s; ++i) sort(all(weight[i]), greater<pair<ll, int>>());

    for(int i = 1; i <= s; ++i){
        for(int j = 1; j <= s; ++j){
            int cur = 0, id = 0, cnt = 0; ll val = 0;
            maximise(dp[i][j], dp[i - 1][j]);
            for(int t = i; t <= j; t += i){
                while(id < (int)weight[i].size() && cur < t){
                    if(cnt >= weight[i][id].second){
                        cnt = 0;
                        id++;
                    }
                    cnt++; cur += i; val += weight[i][id].first;
                }
                if(id >= weight[i].size()) break;
                maximise(dp[i][j], dp[i - 1][j - t] + val);
            }
        }
    }

    ll ans = 0;
    for(int i = 1; i <= s; ++i) maximise(ans, dp[s][i]);

    cout << ans;

    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:43:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |                 if(id >= weight[i].size()) break;
      |                    ~~~^~~~~~~~~~~~~~~~~~~

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