Submission #447727

#	Time	Username	Problem	Language	Result	Execution time	Memory
447727		LptN21	Knapsack (NOI18_knapsack)	C++14	100 / 100	67 ms	3668 KiB

knapsack

#include <bits/stdc++.h>
using namespace std;
#define fastIO ios_base::sync_with_stdio(false), cin.tie(NULL), cout.tie(NULL);
#define FF first
#define SS second
#define pb push_back
#define sz(x) (int)x.size()
#define PI acos(-1.0)
#define lb lower_bound
#define ub upper_bound
#define all(a) (a).begin(), (a).end()
#define odd(x) __builtin_parity((int)x)
#define cntbit(x) __builtin_popcount(x)
typedef long long ll;
typedef pair<int, int> ii;
const int N = 2e3+7, M=5;
const int MOD = 998244353;
const int oo = 1e9;

int n, m, k, t;

int _dp[N];
vector<ii> cmp[N];

signed main() {
    //freopen("test.inp", "r", stdin);
    //freopen("test.out", "w", stdout);
    //fastIO;
    scanf("%d%d", &m, &n); int ans=0;
    for(int j, i=1;i<=n;i++) {
        scanf("%d%d%d", &k, &t, &j);
        cmp[t].pb(ii(k, j));
    }
    memset(_dp, 0, sizeof(int)*(m+1));
    for(int i=1;i<=m;i++) {
        sort(all(cmp[i]));
        for(int j=i;j<=m&&sz(cmp[i]);j+=i) {
            t=cmp[i].back().FF;
            if(!(--cmp[i].back().SS)) cmp[i].pop_back();
            for(int k=m;k>=i;k--) _dp[k]=max(_dp[k], _dp[k-i]+t);
        }
        ans=max(ans, _dp[i]);
    }
    printf("%d", ans);
    return 0;
}
/* stuff you should look for
    - int overflow, array bounds
    - special cases (n=1?)
    - do smth instead of do nothing and stay organized
    - WRITE STUFF DOWN
    - DONT JUST STICK ON ONE APPROACH
*/

Compilation message (stderr)

knapsack.cpp: In function 'int main()':
knapsack.cpp:29:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   29 |     scanf("%d%d", &m, &n); int ans=0;
      |     ~~~~~^~~~~~~~~~~~~~~~
knapsack.cpp:31:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 |         scanf("%d%d%d", &k, &t, &j);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~

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