foo.cc: In function ‘int main()’:
foo.cc:34:21: warning: unused variable ‘a’ [-Wunused-variable]
   34 |                 int a=1,b=1,d=0,e=0;
      |                     ^
foo.cc:34:25: warning: unused variable ‘b’ [-Wunused-variable]
   34 |                 int a=1,b=1,d=0,e=0;
      |                         ^
foo.cc:34:33: warning: unused variable ‘e’ [-Wunused-variable]
   34 |                 int a=1,b=1,d=0,e=0;
      |                                 ^