foo.cc: In function 'int main()':
foo.cc:9:18: warning: unused variable 'j' [-Wunused-variable]
    9 |  long long a,b,i,j,y;
      |                  ^
foo.cc:20:20: warning: 'b' may be used uninitialized in this function [-Wmaybe-uninitialized]
   20 |  cout<<a/b<<"/"<<y/b;
      |                    ^

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