Submission #507511

#	Time	Username	Problem	Language	Result	Execution time	Memory
507511		PikaQ	Knapsack (NOI18_knapsack)	C++17	100 / 100	56 ms	5156 KiB

knapsack

/* RE */
#include<bits/stdc++.h>
#define int ll
#define forn(i,n) for(int i=0;i<(n);i++)
#define Forn(i,n) for(int i=1;i<=(n);i++)
#define ll long long
#define pb push_back
#define F first
#define S second
#define lb lower_bound
#define ub upper_bound
#define rz resize
#define vi vector<int>
#define vl vector<long long>
#define vpi vector<pair<int,int> >
#define pii pair<int,int>
#define pll pair<long long,long long>
#define mp make_pair
#define all(p) p.begin(),p.end()
#define alr(p,q) p+1,p+q+1
#define ull unsigned long long
#define st0(p) memset((p),0,sizeof(p))
#define T(x) ((xb)%2 ? s[(x)/2] : '.')
#define lowb(x) x&-x
#define ls(x) (x)*2
#define rs(x) (x)*2+1
#define sz(x) (x).size()
using namespace std;
 
inline void USACO(const string &s){
  freopen((s+".in").c_str(),"r",stdin);
  freopen((s+".out").c_str(),"w",stdout);
}
 
void debug() {cout << endl;}
template <class T, class ...U> void debug(T a, U ... b) { cout << a << " "; debug(b...);}

#define fail() {cout << "-1\n";return;}
const int mod = 1e9+7;
const int N = 2e3+9;
int n,s;
vpi stuff;
vpi a[N];
int dp[N];

void solve(){
	cin >> s >> n;
	forn(i,n){
		int w,v,k;
		cin >> v >> w >> k;
		a[w].pb(mp(v,k));
	}
	Forn(i,s)	sort(all(a[i]),greater<pii>());
	Forn(i,s){
		int cnt = s/i ;
		for(auto &j : a[i]){
			int res = min(cnt,j.S);
			cnt -= res;
			while(res--){
				// debug(i,j.F);
				stuff.pb(mp(i,j.F));
			}
			if(cnt == 0) break;
		}
	}	
	for(pii p : stuff){
		int w = p.F,v = p.S;
		// debug(w,v);
		for(int i = s;i >= w;i--){
			if(i >= w){
				dp[i] = max(dp[i],dp[i-w] + v);
			}
		}
	}
	int ans = 0;
	cout << dp[s] << '\n';
}
   
 
 
 
signed main(){
  // USACO("feast");
  cin.tie(0);
  cout.tie(0);
  ios_base::sync_with_stdio(0);

 
  // int t;
  // cin >> t;
  // while(t--)
    solve();
 
  return 0;
}

Compilation message (stderr)

knapsack.cpp: In function 'void solve()':
knapsack.cpp:75:6: warning: unused variable 'ans' [-Wunused-variable]
   75 |  int ans = 0;
      |      ^~~

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