Submission #1030507

#	Time	Username	Problem	Language	Result	Execution time	Memory
1030507		LmaoLmao	Knapsack (NOI18_knapsack)	C++17	0 / 100	2 ms	860 KiB

knapsack

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

using ll = long long;
using ii = pair<int, int>;
using aa = array<int,3>;

const int N = 1e6+5;
const int INF = 1e9;

ll dp[2005];
vector<ii> m[2005];
int pre[2005][2005];

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    #ifndef ONLINE_JUDGE
    freopen("in.txt", "r", stdin);
    freopen("out.txt", "w", stdout);
    #endif
    int n,s;
    cin >> s >> n;
    for(int i=1;i<=s;i++) {
        dp[i]=0;
    }
    dp[0]=0;
    for(int i=1;i<=n;i++) {
        int v,w,k;
        cin >> v >> w >> k;
        m[w].push_back({v,k});
    }
    for(int i=1;i<=s;i++) {
        sort(m[i].begin(),m[i].end(),greater<>());
    }
    for(int i=1;i<=s;i++) {
        int cur=0;
        for(ii x:m[i]) {
            int t=cur;
            cur+=x.second*i;
            cur=min(cur,s);
            for(int j=t+i;j<=cur;j+=i) {
                pre[i][j]=pre[i][j-i]+x.first;
            }
            if(cur>=s) break;
        }
        for(int j=1;j<=s;j++) pre[i][j]=max(pre[i][j],pre[i][j-1]);
    }
    ll ans=0;
    for(int i=1;i<=s;i++) {
        for(ll j=s;j>0;j--) {
            for(int k=1;i*k<=j;k++) {
                dp[j]=max(dp[j],dp[j-i*k]+pre[i][i*k]);
                ans=max(ans,dp[j]);
            }
        }
    }
    cout << ans;
    return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:20:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   20 |     freopen("in.txt", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
knapsack.cpp:21:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   21 |     freopen("out.txt", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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