foo.cc: In function 'int main()':
foo.cc:16:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
     for(int i=1;i<=m;i++)
     ^~~
foo.cc:22:6: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
      sort(c,c+n);
      ^~~~
foo.cc:9:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
  ~~~~~^~~~~~~~~~~~~~
foo.cc:12:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d",&a[i].n1,&a[i].m1);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。