Submission #1092444

#	Time	Username	Problem	Language	Result	Execution time	Memory
1092444		juicy	Biochips (IZhO12_biochips)	C++17	80 / 100	301 ms	400980 KiB

biochips

#include <bits/stdc++.h>

using namespace std;

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif

const int N = 2e5 + 5;

int n, m;
int a[N], L[N], R[N], pos[N], dp[N][501];
vector<int> g[N];

int timer;

void dfs(int u) {
  pos[L[u] = ++timer] = u;
  for (int v : g[u]) {
    dfs(v);
  }
  R[u] = timer;
}

int main() {
  ios::sync_with_stdio(false); cin.tie(nullptr);

  cin >> n >> m;
  int rt = -1;
  for (int i = 1; i <= n; ++i) {
    int pr; cin >> pr >> a[i];
    if (!pr) {
      rt = i;
    } else {
      g[pr].push_back(i);
    }
  }  
  dfs(rt);
  for (int i = 1; i <= n; ++i) {
    int u = pos[i];
    for (int j = 0; j <= m; ++j) {
      dp[R[u] + 1][j + 1] = max(dp[R[u] + 1][j + 1], dp[i][j] + a[u]);
      dp[i + 1][j] = max(dp[i + 1][j], dp[i][j]);
    } 
  }
  cout << dp[n][m];
  return 0;
}

• Subtask 1: 80 / 100