Submission #1585993

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;

int n, x, y, a, b, q, d[100001];
vector<int> g[100001];
bool used[100001];

void dfs (int v, int distance) {
  int si = g[v].size(), ret = 0;
  used[v] = true;
  d[v] = distance;
  
  for (int i = 0; i < si; ++i) {
    if (!used[g[v][i]]) {
      dfs(g[v][i], distance + 1);
    }
  }
  used[v] = false;
  
  return;
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);

  cin >> n;
  for (int i = 0; i < n - 1; ++i) {
    cin >> x >> y;
    x--, y--;
    g[x].push_back(y);
    g[y].push_back(x);
  }
  cin >> q;
  for (int i = 0; i < q; ++i) {
    cin >> a >> b;
    a--, b--;
    dfs(a, 0);
    cout << d[b] + 1 << endl;
  }

  return 0;
}

Submission Info

Judge Result