foo.cc: In function 'void dfs(int, int, int)':
foo.cc:16:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |     for (int i=0;i<g[x].size();i++) dfs(g[x][i],minx,x);
      |                  ~^~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:20:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   20 |     scanf("%d%d",&n,&m);
      |     ~~~~~^~~~~~~~~~~~~~
foo.cc:22:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   22 |     for (int i=1;i<=n;i++) scanf("%d",&c[i]);
      |                            ~~~~~^~~~~~~~~~~~
foo.cc:25:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   25 |         scanf("%d%d%d",&t1,&t2,&t3);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~

Found 6 testcases.
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