#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
//~ #define ll int
#define int ll
typedef pair<int32_t, int32_t> pi;
typedef vector <int> vi;
typedef vector <pi> vpi;
typedef pair<pi, ll> pii;
typedef set <ll> si;
typedef long double ld;
#define f first
#define s second
#define mp make_pair
#define FOR(i,s,e) for(int i=s;i<=int(e);++i)
#define DEC(i,s,e) for(int i=s;i>=int(e);--i)
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define lbd(x, y) lower_bound(all(x), y)
#define ubd(x, y) upper_bound(all(x), y)
#define aFOR(i,x) for (auto i: x)
#define mem(x,i) memset(x,i,sizeof x)
#define fast ios_base::sync_with_stdio(false),cin.tie(0),cout.tie(0)
#define maxn 120001
#define INF 1e9
#define MOD 1000000007
typedef pair <vi, int> pvi;
typedef pair <int,pi> ipi;
typedef vector <pii> vpii;
int N,K;
vpi adj[maxn];
int sz[maxn], lvl[maxn],par[maxn][30];
void find_sz(int x, int p){
sz[x] = 1;
aFOR(i,adj[x]) if (i.f != p && lvl[i.f] == -1){
find_sz(i.f,x); sz[x] += sz[i.f];
}
}
int find_cent(int x,int p, int m){
aFOR(i,adj[x]) if (i.f != p && lvl[i.f] == -1 && sz[i.f] > m / 2) return find_cent(i.f,x,m);
return x;
}
bool inc[maxn][30], _dec[maxn][30];
int fi[maxn][30], la[maxn][30]; // All are measured top-down
void find_vals(int x, int p, int d, int incv, int decv, int first_edge, int last_edge){
inc[x][d] = (incv != -1);
_dec[x][d] = (decv != -1);
fi[x][d] = first_edge;
la[x][d] = last_edge;
aFOR(i,adj[x]) if (i.f != p && lvl[i.f] == -1){
int nincv, ndecv, nfirst_edge;
if (incv == -1 || i.s < incv) nincv = -1;
else nincv = i.s;
if (decv == -1 || i.s > decv) ndecv = -1;
else ndecv = i.s;
if (first_edge == -1) nfirst_edge = i.s;
else nfirst_edge = first_edge;
find_vals(i.f, x, d, nincv, ndecv, nfirst_edge, i.s);
}
}
void decomp(int x,int p,int d){
find_sz(x, -1);
int cent = find_cent(x, -1, sz[x]);
lvl[cent] = d;
//~ cout << p << ' ' << cent << '\n';
par[cent][d] = cent;
FOR(i,0,d-1) par[cent][i] = par[p][i];
find_vals(cent, -1, d, 0, N+1, -1, -1);
aFOR(i,adj[cent]) if (lvl[i.f] == -1) decomp(i.f,cent, d+1);
}
char ch;
int a,b;
int32_t main(){
fast;
cin >> N >> K;
int co = 1;
vector <pii> queries;
FOR(i,1,N+K-1){
cin >> ch;
if (ch == 'S'){
cin >> a >> b;
adj[a].pb(pi(b, co)); adj[b].pb(pi(a,co));
co++;
}else if (ch == 'Q'){
cin >> a >> b;
queries.pb(pii(pi(a,b), co-1));
}else{
cin >> a;
queries.pb(pii(pi(a, -1), co-1));
}
}
mem(lvl, -1);
mem(par, -1);
decomp(1,-1,0);
//~ cout << la
//~ return 0;
//~ FOR(i,1,N) cout << lvl[i] << ' ';
//~ cout << '\n';
//~ FOR(i,1,N) cout << par[i][lvl[i]]-1 << ' ';
//~ cout << '\n';
//~ cout << la[5][0];
//~ return 0;
aFOR(i,queries){
if (i.f.s != -1){
int x = i.f.s, y = i.f.f;
if (x == y){
cout << "yes\n"; continue;
}
int lca;
DEC(d,29,0) if (par[x][d] != -1 && par[x][d] == par[y][d]){
lca = par[x][d];
break;
}
//~ cout << lca << ' ';
if (_dec[x][lvl[lca]] && inc[y][lvl[lca]]){
if (fi[x][lvl[lca]] == -1 || la[y][lvl[lca]] == -1 ||
fi[x][lvl[lca]] < la[y][lvl[lca]]){
int last = la[y][lvl[lca]];
if (y == lca) last = fi[x][lvl[lca]];
if (last <= i.s){
cout << "yes\n"; continue;
}
}
}
cout << "no\n";
}
}
}
Compilation message
servers.cpp: In function 'int32_t main()':
servers.cpp:127:23: warning: 'lca' may be used uninitialized in this function [-Wmaybe-uninitialized]
127 | if (_dec[x][lvl[lca]] && inc[y][lvl[lca]]){
| ~~~~~~~^
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
35 ms |
34636 KB |
Output is correct |
| 2 |
Incorrect |
45 ms |
38128 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
35 ms |
34636 KB |
Output is correct |
| 2 |
Incorrect |
45 ms |
38128 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
35 ms |
34692 KB |
Output is correct |
| 2 |
Correct |
168 ms |
106404 KB |
Output is correct |
| 3 |
Correct |
147 ms |
106440 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
35 ms |
34692 KB |
Output is correct |
| 2 |
Correct |
168 ms |
106404 KB |
Output is correct |
| 3 |
Correct |
147 ms |
106440 KB |
Output is correct |
| 4 |
Incorrect |
34 ms |
35652 KB |
Extra information in the output file |
| 5 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
36 ms |
34664 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
36 ms |
34664 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
37 ms |
34604 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
37 ms |
34604 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
42 ms |
34860 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Incorrect |
42 ms |
34860 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
36 ms |
34644 KB |
Output is correct |
| 2 |
Incorrect |
58 ms |
38104 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
36 ms |
34644 KB |
Output is correct |
| 2 |
Incorrect |
58 ms |
38104 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
