Submission #334008

#	Time	Username	Problem	Language	Result	Execution time	Memory
334008		amunduzbaev	Hard route (IZhO17_road)	C++14	19 / 100	9 ms	620 KiB

road

#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define ll long long 
#define ld long double 
#define pii pair<int, int>
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define prc(n) fixed << setprecision(n)
#define fastios ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define pi acos(-1);
const int inf = 1e9+7;
const int N = 105;

vector<vector<int>> edges(N);
int dis[N][N], cur, goal; 
int used[N];
int ds[N];


int ans[N * N];

void dfs(int d, int u, int prev){
	dis[cur][u] = d;
	for(auto x:edges[u]){
		if(x == prev) continue;
		dfs(d+1, x, u);
	}
}

int dfs1(int u, int prev){
	if(u == goal){
		used[u] = 1;
		return 1;
	}
	int mx = 0;
	for(auto x:edges[u]){
		if(x == prev) continue;
		mx = max(dfs1(x, u), mx);
	}
	used[u] = mx;
	return mx;
}

void dfs2(int d, int u, int prev){
	if(used[u]){
		int next = -1;
		for(auto x:edges[u]){
			if(x == prev) continue;
			else if(used[x]) next = x;
			else dfs2(d+1, x, u);
		}
		if(next == -1) return; 
		dfs2(d, next, u);
	}
	
	else{
		ds[u] = d;
		for(auto x:edges[u]){
			if(x == prev) continue;
			dfs2(d+1, x, u);
		}
	}
}

void solve(){
	fastios
	int n;
	cin>>n;
	vector<int>last;
	for(int i=1;i<n;i++){
		int a, b;
		cin>>a>>b;
		edges[a].pb(b);
		edges[b].pb(a);
	}
	for(int i=1;i<=n;i++){
		cur = i;
		dfs(0, i, -1);
		if(sz(edges[i]) == 1) last.pb(i);
	}
	for(int i=0;i<sz(last);i++){
		for(int j=i+1;j<sz(last);j++){				
			cur = last[i], goal = last[j];
			dfs1(cur, -1);
			dfs2(0, cur, -1);
			int mx = 0;
			for(int l=1; l<=n; l++){
				mx = max(mx, ds[l]);
			}
			ans[mx * dis[cur][goal]]++;
			memset(ds, 0, sizeof(ds));
			memset(used, 0, sizeof(used));
		}
	}
	int mx, nm;
	for(int i=(N*N); i>=0; i--){
		if(ans[i]){
			mx = i;
			nm = ans[i];
			break;
		}
	}
	cout<<mx<<" "<<nm<<"\n";
	return;
	
}


 
int main(){
	fastios
	int t = 1;
	//cin>>t;
	while(t--) solve();
	return 0;
}

Compilation message (stderr)

road.cpp: In function 'void solve()':
road.cpp:110:21: warning: 'nm' may be used uninitialized in this function [-Wmaybe-uninitialized]
  110 |  cout<<mx<<" "<<nm<<"\n";
      |                     ^~~~
road.cpp:110:12: warning: 'mx' may be used uninitialized in this function [-Wmaybe-uninitialized]
  110 |  cout<<mx<<" "<<nm<<"\n";
      |            ^~~

• Subtask 1: 19 / 19
• Subtask 2: 0 / 33
• Subtask 3: 0 / 48