Submission #942297

#	Time	Username	Problem	Language	Result	Execution time	Memory
942297		TrendBattles	Knapsack (NOI18_knapsack)	C++14	100 / 100	101 ms	5700 KiB

knapsack

//https://oj.uz/problem/view/NOI18_knapsack

#include <bits/stdc++.h>
using namespace std;
using lli = int64_t;

const lli inf = 0x3f3f3f3f3f3f3f3f;

void maximise(lli& x, lli y) {
    if (x < y) x = y;
}
int main() {
    ios::sync_with_stdio(0); cin.tie(0);
    int n, S; cin >> S >> n;

    vector <vector <int>> value(S + 1);

    for (int i = 1; i <= n; ++i) {
        int v, w, k; cin >> v >> w >> k;

        int pow_2 = 1;
        while (k >= pow_2) {
            if ((lli) w * pow_2 <= S) {
                value[w * pow_2].push_back(v * pow_2);
            }
            k -= pow_2;
            pow_2 <<= 1;
        }

        if (k > 0 and (lli) w * k <= S) {
            value[w * k].push_back(v * k);
        }
    }

    vector <lli> dp(S + 1);

    for (int i = 1; i <= S; ++i) {
        sort(value[i].begin(), value[i].end(), greater <int> ());
        if (value[i].size() > S / i) {
            value[i].erase(value[i].begin() + S / i, value[i].end());
        }
        for (int v : value[i]) {
            for (int j = S; j >= i; --j) {
                maximise(dp[j], dp[j - i] + v);
            }
        }
    }

    cout << dp[S];
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:39:29: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   39 |         if (value[i].size() > S / i) {
      |             ~~~~~~~~~~~~~~~~^~~~~~~

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