foo.cc: In function 'int main()':
foo.cc:4:24: warning: unused variable 'b' [-Wunused-variable]
    4 |  double n,h,g=10.0,t,l,b,a;
      |                        ^
foo.cc:4:26: warning: unused variable 'a' [-Wunused-variable]
    4 |  double n,h,g=10.0,t,l,b,a;
      |                          ^

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