Submission #1102281

#	Time	Username	Problem	Language	Result	Execution time	Memory
1102281		tuannm	Knapsack (NOI18_knapsack)	C++17	73 / 100	1090 ms	2900 KiB

knapsack

#include<bits/stdc++.h>
#define ii pair<int, int>
#define ll pair<long long, long long>
#define fi first
#define se second
#define pb push_back
using namespace std;
const int mod[2] = {1000000007, 998244353};
const int N = 1e5 + 1;
const string NAME = "";
int n, s;
array<int, 3> a[N];
long long dp[N];

template<class X, class Y> bool maximize(X &x, const Y &y) { if (x < y) { x = y; return true; } else return false; }

void inp(){
    cin >> s >> n;

    for(int i = 1; i <= n; ++i)
        cin >> a[i][0] >> a[i][1] >> a[i][2];
}

void solve(){
    for(int i = 1; i <= s; ++i)
        dp[i] = -1e16;

    for(int i = 1; i <= n; ++i){
        for(int w = s; w > 0; --w){
            for(int j = 1; j <= min(a[i][2], w / a[i][1]); ++j)
                maximize(dp[w], dp[w - j * a[i][1]] + 1LL * a[i][0] * j);
        }
    }

    long long ans = 0;
    for(int i = 0; i <= s; ++i)
        maximize(ans, dp[i]);

    cout << ans;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    if(fopen((NAME + ".inp").c_str(), "r")){
        freopen((NAME + ".inp").c_str(), "r", stdin);
        freopen((NAME + ".out").c_str(), "w", stdout);
    }

    inp();
    solve();
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:48:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |         freopen((NAME + ".inp").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:49:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   49 |         freopen((NAME + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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