foo.cc: In function 'int main()':
foo.cc:7:6: warning: unused variable 'a' [-Wunused-variable]
    7 |  int a,b,c,d,n,num1,num2;
      |      ^
foo.cc:7:8: warning: unused variable 'b' [-Wunused-variable]
    7 |  int a,b,c,d,n,num1,num2;
      |        ^
foo.cc:7:10: warning: unused variable 'c' [-Wunused-variable]
    7 |  int a,b,c,d,n,num1,num2;
      |          ^
foo.cc:7:12: warning: unused variable 'd' [-Wunused-variable]
    7 |  int a,b,c,d,n,num1,num2;
      |            ^

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