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Submission #365381

# Submission time Handle Problem Language Result Execution time Memory
365381 2021-02-11T14:36:02 Z FatihSolak Mag (COCI16_mag) C++17
120 / 120
 505 ms 149100 KB 
#include <bits/stdc++.h>
#define N 1000005
using namespace std;
vector<int> adj[N];
int arr[N];
int down[N];
int down2[N];
int d[N];
int up[N];
int maxi = 0,mini = 1e9;
void dfs(int v,int p){
	for(auto u:adj[v]){
		if(u == p)continue;
		dfs(u,v);
		if(arr[u] == 1){
			down[v] = max(down[v],down[u] + 1);
			if(down[v] == down[u] + 1)d[v] = u;
		}
	}
	for(auto u:adj[v]){
		if(u == p)continue;
		if(d[v] != u && arr[u] == 1){
			down2[v] = max(down2[v],down[u]+1);
		}
	}
}
void dfs2(int v,int p){
	if(arr[p] == 1){
		up[v] = up[p] + 1;
		if(arr[v] == 1 && d[p] == v){
			up[v] = max(up[v], down2[p]+1);
		}
		else up[v] = max(up[v], down[p]+1);
	}
	for(auto u:adj[v]){
		if(u == p)continue;
		dfs2(u,v);
	}
}
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	//freopen("in.txt","r",stdin);
	//freopen("out.txt","w",stdout);
	int n;
	cin >> n;
	for(int i=1;i<n;i++){
		int u,v;
		cin >> u >> v;
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
	for(int i=1;i<=n;i++){
		cin >> arr[i];
	}
	dfs(1,0);
	dfs2(1,0);
	for(int i=1;i<=n;i++){
		if(arr[i] == 1){
			maxi = max(maxi,2*(1+down[i]+up[i]));
		}
		if(arr[i] == 2){
			maxi = max(maxi,1+down[i]+up[i]);
		}
		mini = min(mini,arr[i]);
	}
	if(maxi == 0){
		cout << mini << "/" <<1;
	}
	else if(maxi & 1){
		cout << 2 << "/" << maxi;
	}
	else cout << 1 << "/" << maxi/2;
}

Subtask #1
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 23916 KB Output is correct
2 Correct 16 ms 23916 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 23916 KB Output is correct
2 Correct 17 ms 23916 KB Output is correct

Subtask #3
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 401 ms 92780 KB Output is correct

Subtask #4
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 23788 KB Output is correct
2 Correct 505 ms 148064 KB Output is correct

Subtask #5
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 451 ms 146028 KB Output is correct

Subtask #6
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 397 ms 70508 KB Output is correct
2 Correct 291 ms 58476 KB Output is correct

Subtask #7
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 374 ms 71644 KB Output is correct
2 Correct 90 ms 29036 KB Output is correct
3 Correct 465 ms 149100 KB Output is correct

Subtask #8
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 85 ms 29036 KB Output is correct
2 Correct 393 ms 71276 KB Output is correct
3 Correct 359 ms 50028 KB Output is correct

Subtask #9
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 354 ms 67940 KB Output is correct
2 Correct 385 ms 69996 KB Output is correct

Subtask #10
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 397 ms 71300 KB Output is correct
2 Correct 373 ms 50028 KB Output is correct