foo.cc: In function 'void dFs(int)':
foo.cc:31:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   31 |  if(mark[x])top[x]=x;dfn[x]=++cnt;
      |  ^~
foo.cc:31:22: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   31 |  if(mark[x])top[x]=x;dfn[x]=++cnt;
      |                      ^~~
foo.cc: In function 'void calc(int, int, int)':
foo.cc:41:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   41 |  if(!v[w[x]])bt[w[x]]=1,sum++;v[w[x]]++;
      |  ^~
foo.cc:41:31: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   41 |  if(!v[w[x]])bt[w[x]]=1,sum++;v[w[x]]++;
      |                               ^
foo.cc: In function 'int main()':
foo.cc:53:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   53 |  scanf("%d%d",&n,&m);
      |  ~~~~~^~~~~~~~~~~~~~
foo.cc:55:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   55 |   scanf("%d",&w[i]),b[i]=w[i];
      |   ~~~~~^~~~~~~~~~~~
foo.cc:62:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   62 |   scanf("%d%d",&x,&y);
      |   ~~~~~^~~~~~~~~~~~~~
foo.cc:71:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   71 |   scanf("%d%d",&x,&y);
      |   ~~~~~^~~~~~~~~~~~~~

Found 4 testcases.
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