foo.cc: In function 'int main()':
foo.cc:7:14: warning: unused variable 'j' [-Wunused-variable]
    7 |  int a,b,c,i,j,n,y;
      |              ^
foo.cc:17:8: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   17 |  cout<<y;
      |        ^

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