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Submission #133444

# Submission time Handle Problem Language Result Execution time Memory
133444 2019-07-20T17:13:49 Z tdwn Mag (COCI16_mag) C++17
120 / 120
 1925 ms 203996 KB 
#include <bits/stdc++.h>
#define ll long long 
#define pb push_back
#define mp make_pair
using namespace std;
const int maxn = 1000100;
vector<int>g[maxn];
ll arr[maxn], n;
ll result1;
ll result2;
 
ll dp[maxn][2];
 
void dfs(int node, int p) {
	if(arr[node] == 1) dp[node][0] = 1;
	if(arr[node] == 2) dp[node][1] = 1;



	vector<ll>v;

	ll max_0 = dp[node][0];
	ll max_1 = dp[node][1];

	for(int i:g[node]) {
		if(i != p) {
			dfs(i, node);

			if(arr[node] == 1) {
				if(arr[i] == 1) {
					dp[node][0] = max(dp[node][0], 1 + dp[i][0]);
					v.pb(dp[i][0]);
				}
				if(dp[i][1] != 0) dp[node][1] = max(dp[node][1], 1 + dp[i][1]);
			}
			else if(arr[node] == 2) {
				dp[node][1] = max(dp[node][1], 1 + dp[i][0]);
			}

			//cout<<"Updating "<<node<<" from "<<i<<" - "<<dp[i][0]<<" "<<dp[i][1]<<"\n";

			result2 = max(result2, max_0 + dp[i][1]);
			result2 = max(result2, max_1 + dp[i][0]);

			max_0 = max(max_0, dp[node][0]);
			max_1 = max(max_1, dp[node][1]);
		}
	}

	result1 = max(result1, dp[node][0]);
	result2 = max(result2, dp[node][1]);

	v.pb(0);
	v.pb(0);
	sort(v.rbegin(), v.rend());

	if(arr[node] == 2) {
		result2 = max(result2, v[0] + v[1] + 1);
	}
	else if(arr[node] == 1) {
		result1 = max(result1, v[0] + v[1] + 1);
	}

}
 
int main() {
	cin>>n;
	ll a, b;
	for(int i=0;i<n-1;i++) {
		cin>>a>>b;
		g[a].pb(b);
		g[b].pb(a);
	}
 
	ll minval = LLONG_MAX;
	for(int i=1;i<=n;i++) {
		cin>>arr[i];
		minval = min(minval, arr[i]);
	}
 
	if(minval != 1) {
		cout<<minval<<"/1\n";
	}
	else {
		dfs(1, -1);
		if(result2 > 2*result1) {
			cout<<"2/"<<result2<<"\n";
		}
		else {
			cout<<"1/"<<result1<<"\n";
		}
	}
}

Subtask #1
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 24 ms 23928 KB Output is correct
2 Correct 24 ms 23928 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 24 ms 23800 KB Output is correct
2 Correct 25 ms 23928 KB Output is correct

Subtask #3
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1494 ms 117864 KB Output is correct

Subtask #4
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 23800 KB Output is correct
2 Correct 1779 ms 202424 KB Output is correct

Subtask #5
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1841 ms 199540 KB Output is correct

Subtask #6
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1726 ms 78408 KB Output is correct
2 Correct 1233 ms 64248 KB Output is correct

Subtask #7
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1745 ms 79424 KB Output is correct
2 Correct 227 ms 29404 KB Output is correct
3 Correct 1925 ms 203996 KB Output is correct

Subtask #8
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 216 ms 29432 KB Output is correct
2 Correct 1685 ms 79456 KB Output is correct
3 Correct 1029 ms 52048 KB Output is correct

Subtask #9
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1590 ms 75712 KB Output is correct
2 Correct 1747 ms 77744 KB Output is correct

Subtask #10
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 1750 ms 79516 KB Output is correct
2 Correct 1054 ms 51884 KB Output is correct