/in/foo.cc: In function 'int main()':
/in/foo.cc:45:7: warning: unused variable 'a1' [-Wunused-variable]
   int a1=a[0],a2=a[1];
       ^~
/in/foo.cc:45:15: warning: unused variable 'a2' [-Wunused-variable]
   int a1=a[0],a2=a[1];
               ^~