Submission #230424

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Source Code Expand

#include<cstdio>
#include<cstring>
#include<map>
#include<vector>
#include<algorithm>
using namespace std;

int x, y;
//int memo[100010];
int dp[100010];
map<pair<int, int>, int> memo;
bool used[100010];
vector<int> v[100010];

int dist(int p, int cnt)
{
  if(dp[p]) return dp[p];
  if(dp[p]) return dp[p];
  if(p == y) return 0;
  if(used[p]) return 999999;
  
  int ret = 999999; used[p] = true;
  for(int i = 0;i < v[p].size(); i++)
    ret = min(ret, dist(v[p][i], cnt + 1) + 1);

  memo[make_pair(x, p)] = memo[make_pair(p, x)] = cnt;
  return dp[p] = ret;
}

int main(void)
{
  int n, q, a, b;

  scanf("%d", &n);
  for(int i = 0;i < n - 1; i++){
    scanf("%d %d", &x, &y);
    v[x].push_back(y);
    v[y].push_back(x);
  }
  scanf("%d", &q);
  for(int i = 0;i < q; i++){
    scanf("%d %d", &x, &y);
 
    memset(used, false, sizeof(used));
    memset(dp, 0, sizeof(dp));
    if(memo[make_pair(x, y)])
      printf("%d\n", memo[make_pair(x, y)]);
    else
      printf("%d\n", dist(x, 1) + 1);
  }

}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:34:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
./Main.cpp:36:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
./Main.cpp:40:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
./Main.cpp:42:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]

Judge Result