foo.cc: In function 'int main()':
foo.cc:18:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for ( int i = 0 ; i < strlen(in1) ; i ++ )
                    ~~^~~~~~~~~~~~~
foo.cc:46:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for ( int i = 0 ; i < strlen(mission) ; i ++ )
                    ~~^~~~~~~~~~~~~~~~~

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