Submission #1025012

#	Time	Username	Problem	Language	Result	Execution time	Memory
1025012		yellowtoad	Power Plant (JOI20_power)	C++17	100 / 100	219 ms	30284 KiB

power

#include <iostream>
#include <vector>
using namespace std;

int n, dp[200010], b[200010], dpp[200010], ans;
vector<int> edge[200010];
char ch;

void dfs(int u, int v) {
	for (int i = 0; i < edge[u].size(); i++) {
		if (edge[u][i] != v) {
			dfs(edge[u][i],u);
			dp[u] += dp[edge[u][i]];
		}
	}
	if (b[u]) dp[u] = max(dp[u]-1,1);
}

void dfs1(int u, int v, int maxx) {
	int sum = 0;
	dpp[u] = dp[u]+maxx;
	for (int i = 0; i < edge[u].size(); i++) if (edge[u][i] != v) sum += dp[edge[u][i]];
	for (int i = 0; i < edge[u].size(); i++) if (edge[u][i] != v) dfs1(edge[u][i],u,(b[u] ? max(maxx+sum-dp[edge[u][i]]-1,1) : maxx+sum-dp[edge[u][i]]));
}

int main() {
	cin >> n;
	for (int i = 1; i < n; i++) {
		int u, v;
		cin >> u >> v;
		edge[u].push_back(v);
		edge[v].push_back(u);
	}
	for (int i = 1; i <= n; i++) {
		cin >> ch;
		b[i] = ch-'0';
	}
	dfs(1,0);
	dfs1(1,0,0);
	for (int i = 1; i <= n; i++) ans = max(ans,dpp[i]);
	cout << ans << endl;
}

Compilation message (stderr)

power.cpp: In function 'void dfs(int, int)':
power.cpp:10:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |  for (int i = 0; i < edge[u].size(); i++) {
      |                  ~~^~~~~~~~~~~~~~~~
power.cpp: In function 'void dfs1(int, int, int)':
power.cpp:22:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |  for (int i = 0; i < edge[u].size(); i++) if (edge[u][i] != v) sum += dp[edge[u][i]];
      |                  ~~^~~~~~~~~~~~~~~~
power.cpp:23:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |  for (int i = 0; i < edge[u].size(); i++) if (edge[u][i] != v) dfs1(edge[u][i],u,(b[u] ? max(maxx+sum-dp[edge[u][i]]-1,1) : maxx+sum-dp[edge[u][i]]));
      |                  ~~^~~~~~~~~~~~~~~~

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