/in/foo.c: In function 'Merge':
/in/foo.c:21:5: warning: 'main' is normally a non-static function [-Wmain]
 int main()
     ^~~~
/in/foo.c:42:1: error: expected declaration or statement at end of input
 }
 ^
/in/foo.c:42:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
At top level:
/in/foo.c:21:5: warning: 'main' defined but not used [-Wunused-function]
 int main()
     ^~~~