foo.c: In function 'main':
foo.c:5:23: warning: unused variable 'e' [-Wunused-variable]
    5 |   int a=0,b=0,c=0,d=0,e=0,f=1,n=0;
      |                       ^
foo.c:5:11: warning: variable 'b' set but not used [-Wunused-but-set-variable]
    5 |   int a=0,b=0,c=0,d=0,e=0,f=1,n=0;
      |           ^

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