Submission #446051

#	Time	Username	Problem	Language	Result	Execution time	Memory
446051		MaisyDoge13	Knapsack (NOI18_knapsack)	C++17	73 / 100	892 ms	262148 KiB

knapsack

#include <iostream>
#include <cstdio>
#include <vector>
#include <utility>
#include <cmath>
#include <algorithm>
#include <array>
#include <set>
#include <climits>
#include <map>
#include <memory>
#include <string>
#include <deque>
#include <queue>
#include <stack>
using namespace std;

#define input "knapsack.in"
#define output "knapsack.out"
#define int long long
#define double long double
typedef tuple<double, int, int, int> item;
int S, n;
vector<item> items;
vector<vector<int>> dp;
signed main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    //freopen(input, "r", stdin);
    //freopen(output, "w", stdout);
    cin >> S >> n;
    dp.resize(S+1, vector<int>(n+1, 0));
    items.reserve(n);
    for (int i=0;i<n;i++) {
        int val, weight, amt;
        cin >> val >> weight >> amt;
        items.push_back({(double)(val)/weight, val, weight, amt});
    }
    sort(items.begin(), items.end(), [](item& a, item& b) -> bool {
        return get<0>(a)<get<0>(b);
    });
    /* for (int i=0;i<n;i++) cout << get<0>(items[i]) << ' ' << get<1>(items[i]) <<
    ' ' << get<2>(items[i]) << ' ' << get<3>(items[i]) << endl; */
    for (int i=0;i<n;i++) dp[get<2>(items[i])][i+1]=get<1>(items[i]);
    for (int s=1;s<=S;s++) {
        for (int i=1;i<=n;i++) {
            dp[s][i]=max(dp[s-1][i], dp[s][i]);
            int amt=get<3>(items[i-1]), wt=get<2>(items[i-1]), val=get<1>(items[i-1]);
            for (int k=0;k<=s && k/wt<=amt;k+=wt) {
                int used=k/wt*val;
                dp[s][i]=max(dp[s][i], used+dp[s-k][i-1]);
            }
        }
    }
    cout << dp[S][n] << endl;
}

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