foo.c: In function 'main':
foo.c:4:10: warning: variable 'ws' set but not used [-Wunused-but-set-variable]
  int a=0,ws=0,i=0,x=1,first=1,a1;
          ^~
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&a);
  ^~~~~~~~~~~~~~

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