Submission #1589893

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Source Code Expand

#include <iostream>
#include <cstdio>
#include <vector>
using namespace std;

const int MAX = 1e5;
const int INF = 1e9;
int d[MAX];
vector<vector<int> > edge(MAX);

void dfs(int s, int g) {
  for (int i = 0; i < edge[s].size(); i++) {
    if (d[edge[s][i]] < INF) continue;
    d[edge[s][i]] = d[s] + 1;
    if (edge[s][i] == g) return;
    
    dfs(edge[s][i], g);
  }
}

int main() {
  int N;
  cin >> N;
  int x, y;
  for (int i = 0; i < N - 1; i++) {
    scanf("%d %d", &x, &y);
    x--; y--;
    edge[x].push_back(y);
    edge[y].push_back(x);
  }

  int Q;
  cin >> Q;
  int a, b;
  for (int i = 0; i < Q; i++) {
    cin >> a >> b;
    a--; b--;
    fill(d, d + MAX, INF);
    d[a] = 0;
    dfs(a, b);

    // 解答
    printf("%d\n", d[b] + 1);
  }

  return 0;
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:26:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &x, &y);
                           ^

Judge Result