Submission #532750

#	Time	Username	Problem	Language	Result	Execution time	Memory
532750		Alex_tz307	Power Plant (JOI20_power)	C++17	100 / 100	183 ms	28792 KiB

power

#include <bits/stdc++.h>

using namespace std;

const int kN = 2e5;
vector<int> g[1 + kN];
string s;
int ans, dp[1 + kN];

void maxSelf(int &x, int y) {
  if (x < y) {
    x = y;
  }
}

void dfs(int u, int par) {
  int best = 0, sum = 0;
  for (int v : g[u]) {
    if (v != par) {
      dfs(v, u);
      maxSelf(best, dp[v]);
      sum += dp[v];
    }
  }
  maxSelf(ans, max(best + (s[u] - '0'), sum - (s[u] - '0')));
  dp[u] = max(s[u] - '0', sum - (s[u] - '0'));
}

void testCase() {
  int n;
  cin >> n;
  for (int i = 1; i < n; ++i) {
    int u, v;
    cin >> u >> v;
    g[u].emplace_back(v);
    g[v].emplace_back(u);
  }
  cin >> s;
  s = '$' + s;
  dfs(1, 0);
  cout << ans << '\n';
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  int tests = 1;
  for (int tc = 0; tc < tests; ++tc) {
    testCase();
  }
  return 0;
}

• Subtask 1: 6 / 6
• Subtask 2: 41 / 41
• Subtask 3: 53 / 53