foo.cc: In function 'int main()':
foo.cc:25:7: warning: unused variable 'k' [-Wunused-variable]
   int k=i;
       ^
foo.cc: In function 'int ss(int)':
foo.cc:15:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
foo.cc: In function 'int main()':
foo.cc:40:6: warning: 'imax' may be used uninitialized in this function [-Wmaybe-uninitialized]
  cout<<imax; 
  ~~~~^~~~~~

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