foo.cc: In function 'int main()':
foo.cc:35:10: warning: unused variable 'v' [-Wunused-variable]
  int a,b,v,i,s=0;
          ^
foo.cc: In function 'int hu(int)':
foo.cc:32:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

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