foo.cc: In function 'int visit(int, int, int)':
foo.cc:22:5: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
   22 |     else
      |     ^~~~
foo.cc:24:3: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'else'
   24 |   for(int i=0;i<ve[begin].size();i++)
      |   ^~~
foo.cc:24:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |   for(int i=0;i<ve[begin].size();i++)
      |               ~^~~~~~~~~~~~~~~~~
foo.cc: At global scope:
foo.cc:42:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   42 | main()
      |      ^

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