Submission #435928

#	Time	Username	Problem	Language	Result	Execution time	Memory
435928		cgiosy	Biochips (IZhO12_biochips)	C++17	0 / 100	1 ms	1868 KiB

biochips

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

void mx(int&a, int b) { a=max(a, b); }
int main() {
	ios::sync_with_stdio(0);cin.tie(0);
	int N, K, r;
	cin>>N>>K;
	int D[2][200004], F[N+1], G[N+1]{}, W[N+1];
	for(int i=1; i<=N; i++) {
		int p;
		cin>>p>>W[i];
		if(p) F[i]=G[p], G[p]=i;
		else r=i;
	}
	int n[2]{}, d=0;
	function<int(int)> dfs=[&](int i) {
		int p=n[d];
		for(int e=G[i]; e; e=F[e]) {
			d^=1;
			int m=dfs(e);
			d^=1;
			int q=n[d^1]-=m, j=min(n[d]-p+m, K);
			for(int k=n[d]; k<p+j; k++) D[d][k]=-1e9;
			n[d]=p+j;
			while(--j) for(int k=min(m, j); k--;)
				mx(D[d][p+j], D[d][p+j-k-1]+D[d^1][q+k]);
			for(int k=0; k<m; k++) mx(D[d][p+k], D[d^1][q+k]);
		}
		if(p==n[d]) D[d][n[d]++]=W[i];
		else mx(D[d][p], W[i]);
		return n[d]-p;
	};dfs(r);
	cout<<D[0][K-1]<<'\n';
}

Compilation message (stderr)

biochips.cpp: In function 'int main()':
biochips.cpp:7:12: warning: 'r' may be used uninitialized in this function [-Wmaybe-uninitialized]
    7 |  int N, K, r;
      |            ^

• Subtask 1: 0 / 100