Submission #755535

#	Time	Username	Problem	Language	Result	Execution time	Memory
755535		3omar_ahmed	Knapsack (NOI18_knapsack)	C++17	100 / 100	943 ms	35688 KiB

knapsack

/**
 * author: 3omar_ahmed
 * date: 09-06-2023
 * ya rb awsl CM :)
 */
#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
using namespace std ;
#define int long long
#define endl '\n'
#define all(a) a.begin() , a.end()
#define alr(a) a.rbegin() , a.rend()
int x, n;
vector < vector < int >> dp;
vector < vector < pair < int , int >>> a;
int DP(int idx, int still) {
    if(still == 0 || idx == x) return 0;
    if(dp[idx][still] != -1) return dp[idx][still];
    int op1 = DP(idx + 1, still);
    int op2 = 0, sum = 0, val = 0;
    for(int i = 0 ; i < a[idx].size() ; i++) {
        for(int j = 0 ; j < a[idx][i].second ; j++) {
            sum += idx + 1, val += a[idx][i].first;
            if(sum > still) break;
            op2 = max(op2, DP(idx + 1, still - sum) + val);
        }
    }
    return dp[idx][still] = max(op1, op2);
} 
signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0);cout.tie(0);

    cin >> x >> n;
    a = vector < vector < pair < int , int >>> (x + 1);
    for(int i = 0 ; i < n ; i++) {
        int b, c, d;
        cin >> b >> c >> d;
        a[c - 1].push_back({b, d});
    }
    dp = vector < vector < int >> (x + 2, vector < int > (x + 2, -1));
    for(auto &i : a) sort(alr(i));
    cout << DP(0, x) << endl;
    return 0 ;
}

Compilation message (stderr)

knapsack.cpp: In function 'long long int DP(long long int, long long int)':
knapsack.cpp:21:23: 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]
   21 |     for(int i = 0 ; i < a[idx].size() ; i++) {
      |                     ~~^~~~~~~~~~~~~~~

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