Submission #581959

#	Time	Username	Problem	Language	Result	Execution time	Memory
581959		Belgutei	Knapsack (NOI18_knapsack)	C++17	100 / 100	66 ms	2896 KiB

knapsack

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

#define ll long long
#define ff first
#define ss second
#define pb push_back
#define IOS ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); 

int s,n;
ll val, wei, num;
vector<pair<ll,ll>> p[2005];
vector<ll> v[2005];
ll dp[2005];
ll ans;

int main() {
    IOS
    cin >> s >> n; // s <= 2000
    for(int i = 1; i <= n; i ++) {
        cin >> val >> wei >> num; 
        p[wei].pb({-val, num});
    }
    for(int i = 1; i <= s; i ++) {
        sort(p[i].begin(), p[i].end());
        int tmp = s / i;
        int pos = 0;
        while(tmp > 0 && pos < p[i].size()) {
            if(p[i][pos].ss == 0) {
                pos ++;
                continue;
            }
            tmp --;
            v[i].pb(-p[i][pos].ff);
            p[i][pos].ss --;
        }
    }
    for(int i = 1; i <= s; i ++) { // weight
        for(int j = s; j >= 0; j --) {
            ll tmp = 0;
            for(int k = 0; k < v[i].size(); k ++) {
                if(j - (k + 1) * i < 0) break;
                tmp += v[i][k];
                dp[j] = max(dp[j], dp[j - (k + 1) * i] + tmp);
                ans = max(ans, dp[j]);
            }
        }
    }
    cout << ans;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:28:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   28 |         while(tmp > 0 && pos < p[i].size()) {
      |                          ~~~~^~~~~~~~~~~~~
knapsack.cpp:41:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |             for(int k = 0; k < v[i].size(); k ++) {
      |                            ~~^~~~~~~~~~~~~

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