Submission #1128404

#	Time	Username	Problem	Language	Result	Execution time	Memory
1128404		tuongll	Knapsack (NOI18_knapsack)	C++17	100 / 100	63 ms	1888 KiB

knapsack

#include <iostream>
#include <cstring>
#include <algorithm>
#include <vector>
#include <utility>
#include <cmath>
#include <ctime>
#include <cassert>
#include <set>
#include <stack>
#include <map>
#include <queue>
#include <random>
#include <chrono>
#include <bitset>
#include <array>
#include <sstream>
#include <limits>
using ll = long long;
#define debug(x) cout << #x << " = " << x << '\n'
#define separator "===============================================\n"
#define all(a) a.begin(), a.end()
#define SZ(a) (int)(a).size()
using namespace std;
const int mxn = 2e3 + 3;
const ll  mod = 1e9 + 7;
const int inf32 = 2e9;
const ll  inf64 = 7e18;
// #pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
int S, n;
vector<pair<int, int>> items[mxn], cand;
int dp[mxn], new_dp[mxn];
void solve(){
    cin >> S >> n;
    for (int i = 1, v, w, k; i <= n; ++i){
        cin >> v >> w >> k;
        items[w].emplace_back(v, k);
    }
    for (int w = 1; w <= S; ++w){
        sort(all(items[w]), greater<>());
        int needed = (S + w - 1) / w;
        for (auto item : items[w]){
            int v, k; tie(v, k) = item;
            int taken = min(k, needed);
            for (int i = 0; i < taken; ++i)
                cand.emplace_back(w, v);
            needed -= taken;
        }
    }
    for (auto item : cand){
        int w, v; tie(w, v) = item;
        for (int i = 0; i <= S; ++i){
            new_dp[i] = dp[i];
            if (i >= w) new_dp[i] = max(new_dp[i], dp[i - w] + v);
        }
        for (int i = 0; i <= S; ++i)
            dp[i] = new_dp[i];
    }
    cout << dp[S];
}
int main(){
    auto start = chrono::steady_clock::now();
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int t = 1;
    // cin >> t;
    while(t--) solve();
    chrono::duration<double> elapsed {chrono::steady_clock::now() - start};
    cerr << "\n>> Runtime: " << elapsed.count() << "s\n";
}

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