#include <bits/stdc++.h>
using namespace std;
// macros
typedef long long ll;
typedef long double ld;
typedef pair<int, int> ii;
typedef pair<ll, ll> lll;
typedef tuple<int, int, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<iii> viii;
typedef vector<ll> vll;
typedef vector<lll> vlll;
#define REP(a,b,c) for(int a=int(b); a<int(c); a++)
#define RE(a,c) REP(a,0,c)
#define RE1(a,c) REP(a,1,c+1)
#define REI(a,b,c) REP(a,b,c+1)
#define REV(a,b,c) for(int a=int(c-1); a>=int(b); a--)
#define FOR(a,b) for(auto& a : b)
#define all(a) a.begin(), a.end()
#define INF 1e9
#define EPS 1e-9
#define pb push_back
#define popb pop_back
#define fi first
#define se second
#define sz size()
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
// input
template<class T> void IN(T& x) {cin >> x;}
template<class H, class... T> void IN(H& h, T&... t) {IN(h); IN(t...); }
// output
template<class T1, class T2> void OUT(const pair<T1,T2>& x);
template<class T> void OUT(const T& x) {cout << x;}
template<class H, class... T> void OUT(const H& h, const T&... t) {OUT(h); OUT(t...); }
template<class T1, class T2> void OUT(const pair<T1,T2>& x) {OUT(x.fi,' ',x.se);}
template<class... T> void OUTL(const T&... t) {OUT(t..., "\n"); }
template<class H> void OUTLS(const H& h) {OUTL(h); }
template<class H, class... T> void OUTLS(const H& h, const T&... t) {OUT(h,' '); OUTLS(t...); }
//===================//
// Added libraries //
//===================//
//===================//
//end added libraries//
//===================//
void program();
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
program();
}
//===================//
// begin program //
//===================//
const int MX = 1e6+10;
int n, t, m;
int a[MX], b[MX];
vi adj[MX];
vi path;
bool dfsPath(int u, int p=-1) {
if(u == 1) {
path.pb(u);
return 1;
}
FOR(v,adj[u]) if(v != p) {
if(dfsPath(v,u)) {
path.pb(u);
return 1;
}
}
return 0;
}
int dp[MX];
void dfsDP(int u, int p=-1) {
FOR(v,adj[u]) if(v != p) dfsDP(v,u);
vi res;
FOR(v,adj[u]) if(v != p) {
res.pb(dp[v]+1);
}
sort(all(res));
if(res.sz <= 1) dp[u] = res.sz;
else dp[u] = res[1]+res.sz-1;
}
void program() {
IN(n,t,m);
RE(i,n-1) IN(a[i], b[i]);
RE(i,n) adj[a[i]].pb(b[i]);
RE(i,n) adj[b[i]].pb(a[i]);
dfsPath(m);
reverse(all(path));
dfsDP(m,t);
OUTL(dp[m]);
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
15 ms |
23808 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
365 ms |
73596 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
15 ms |
23808 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
15 ms |
23808 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |