Submission #2197187
Source Code Expand
#include <bits/stdc++.h>
using namespace std;
//#define int long long
#define reps(i,s,n) for(int (i)=(s);(i)<(n);++(i))
#define rep(i,n) reps(i,0,n)
#define rept(i,n) reps(i,0,((n)+1))
#define repst(i,s,n) reps(i,s,((n)+1))
#define reprt(i,n,t) for(int (i)=(n);(i)>=(t);--(i))
#define repr(i,n) reprt(i,n,0)
#define each(itr,v) for(auto &(itr):(v))
#define all(c) (c).begin(),(c).end()
#define pb push_back
#define mp(x,y) make_pair((x),(y))
#define fi first
#define se second
#define tmax(x,y,z) max(x,max(y,z))
#define tmin(x,y,z) min(x,min(y,z))
#define chmin(x,y) x=min(x,y)
#define chmax(x,y) x=max(x,y)
#define ln '\n'
#define bln(i,n) (i==n-1?'\n':' ')
#define dbg(x) cout<<#x" = "<<(x)<<ln
#define dbga(x,n) {cout<<#x" : ";for(int (i)=0;i<(n);++i){cout<<((x)[i])<<(i==((n)-1)?'\n':' ');}}
typedef long double ld;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<string> vst;
typedef vector<bool> vb;
typedef vector<ld> vld;
typedef vector<pii> vpii;
typedef vector<pll> vpll;
typedef vector<vector<int> > mat;
const ll inf = (ll)1e9+10;
const ll linf = (ll)1e18+10;
const ll mod = (ll)(1e9+7);
const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};
const int ddx[] = {0, 1, 1, 1, 0, -1, -1, -1};
const int ddy[] = {1, 1, 0, -1, -1, -1, 0, 1};
const double eps = 1e-10;
struct oreno_initializer {
oreno_initializer() {
cin.tie(0);
ios::sync_with_stdio(0);
}
} oreno_initializer;
// ━━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…
// .。.:( ^ω^)・゚+.。.:( ^ω^)・゚+.。.:( ^ω^)・゚+.。.:( ^ω^)・゚+.。.:( ^ω^)・゚+
// ・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・‥…━━━☆・
const int MAX_V = 100100;
int n, a, b, q;
vi G[MAX_V];
int root; // 根ノードの番号
int parent[20][MAX_V]; // parent[k][i]: iの親を2^k回辿って到達する頂点 (根を通り過ぎる場合は-1)
int depth[MAX_V]; // 根からの深さ
void LCAdfs(int v, int p, int d) {
parent[0][v] = p;
depth[v] = d;
for (int i = 0; i < G[v].size(); ++i) {
if (G[v][i] != p) LCAdfs(G[v][i], v, d+1);
}
}
// LCAの初期化
void LCAinit(int V) {
// parent[0](真上の親)とdepthを初期化する
LCAdfs(root, -1, 0);
// parent[k](k>=1)を初期化する
for (int k = 0; k+1 < 20; ++k) {
for (int v = 0; v < V; ++v) {
if (parent[k][v] < 0) parent[k+1][v] = -1;
else parent[k+1][v] = parent[k][parent[k][v]];
}
}
}
// 2頂点のLCAを求める
int LCA(int u, int v) {
// uとvの深さが同じになるまで親を辿る
if (depth[u] > depth[v]) swap(u, v);
for (int k = 0; k < 20; ++k) {
if ((depth[v]-depth[u])>>k & 1) v = parent[k][v];
}
if (u == v) return u;
// 二分探索でLCAを求める
for (int k = 19; k >= 0; --k) {
if (parent[k][u] != parent[k][v]) {
u = parent[k][u];
v = parent[k][v];
}
}
return parent[0][u];
}
signed main() {
cin >> n;
rep(i,n-1) {
cin >> a >> b;
a--, b--;
G[a].pb(b), G[b].pb(a);
}
LCAinit(n);
cin >> q;
while (q--) {
cin >> a >> b;
a--, b--;
int p = LCA(a,b);
cout << depth[a]+depth[b]-2*depth[p]+1 << ln;
}
}
Submission Info
Submission Time |
|
Task |
D - 閉路 |
User |
creep04 |
Language |
C++14 (GCC 5.4.1) |
Score |
100 |
Code Size |
3543 Byte |
Status |
AC |
Exec Time |
118 ms |
Memory |
20864 KB |
Judge Result
Set Name |
Sample |
Subtask1 |
Subtask2 |
Score / Max Score |
0 / 0 |
30 / 30 |
70 / 70 |
Status |
|
|
|
Set Name |
Test Cases |
Sample |
subtask0_sample01.txt, subtask0_sample02.txt, subtask0_sample03.txt |
Subtask1 |
subtask1_01.txt, subtask1_02.txt, subtask1_03.txt, subtask1_04.txt, subtask1_05.txt, subtask1_06.txt, subtask1_07.txt, subtask1_08.txt, subtask1_09.txt, subtask1_10.txt, subtask1_11.txt, subtask1_12.txt |
Subtask2 |
subtask0_sample01.txt, subtask0_sample02.txt, subtask0_sample03.txt, subtask1_01.txt, subtask1_02.txt, subtask1_03.txt, subtask1_04.txt, subtask1_05.txt, subtask1_06.txt, subtask1_07.txt, subtask1_08.txt, subtask1_09.txt, subtask1_10.txt, subtask1_11.txt, subtask1_12.txt, subtask2_01.txt, subtask2_02.txt, subtask2_03.txt, subtask2_04.txt, subtask2_05.txt, subtask2_06.txt, subtask2_07.txt, subtask2_08.txt, subtask2_09.txt, subtask2_10.txt, subtask2_11.txt, subtask2_12.txt |
Case Name |
Status |
Exec Time |
Memory |
subtask0_sample01.txt |
AC |
3 ms |
8832 KB |
subtask0_sample02.txt |
AC |
3 ms |
8832 KB |
subtask0_sample03.txt |
AC |
3 ms |
8832 KB |
subtask1_01.txt |
AC |
35 ms |
20224 KB |
subtask1_02.txt |
AC |
35 ms |
20224 KB |
subtask1_03.txt |
AC |
3 ms |
8832 KB |
subtask1_04.txt |
AC |
3 ms |
8832 KB |
subtask1_05.txt |
AC |
3 ms |
8832 KB |
subtask1_06.txt |
AC |
3 ms |
8832 KB |
subtask1_07.txt |
AC |
43 ms |
14080 KB |
subtask1_08.txt |
AC |
43 ms |
13952 KB |
subtask1_09.txt |
AC |
47 ms |
13952 KB |
subtask1_10.txt |
AC |
43 ms |
13952 KB |
subtask1_11.txt |
AC |
44 ms |
13952 KB |
subtask1_12.txt |
AC |
43 ms |
13952 KB |
subtask2_01.txt |
AC |
59 ms |
20864 KB |
subtask2_02.txt |
AC |
60 ms |
20736 KB |
subtask2_03.txt |
AC |
28 ms |
8960 KB |
subtask2_04.txt |
AC |
31 ms |
9088 KB |
subtask2_05.txt |
AC |
37 ms |
9216 KB |
subtask2_06.txt |
AC |
37 ms |
9216 KB |
subtask2_07.txt |
AC |
85 ms |
14336 KB |
subtask2_08.txt |
AC |
90 ms |
14336 KB |
subtask2_09.txt |
AC |
95 ms |
14336 KB |
subtask2_10.txt |
AC |
118 ms |
14336 KB |
subtask2_11.txt |
AC |
106 ms |
14336 KB |
subtask2_12.txt |
AC |
100 ms |
14336 KB |