foo.c: In function 'main':
foo.c:7:10: warning: format '%d' expects argument of type 'int *', but argument 2 has type 'int' [-Wformat=]
  scanf("%d%d%d",a,b,c);
         ~^
foo.c:7:12: warning: format '%d' expects argument of type 'int *', but argument 3 has type 'int' [-Wformat=]
  scanf("%d%d%d",a,b,c);
           ~^
foo.c:7:14: warning: format '%d' expects argument of type 'int *', but argument 4 has type 'int' [-Wformat=]
  scanf("%d%d%d",a,b,c);
             ~^
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ^~~~~~~~~~~~~~
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d",a,b,c);
  ^~~~~~~~~~~~~~~~~~~~~
foo.c:7:2: warning: 'a' is used uninitialized in this function [-Wuninitialized]
  scanf("%d%d%d",a,b,c);
  ^~~~~~~~~~~~~~~~~~~~~
foo.c:7:2: warning: 'b' is used uninitialized in this function [-Wuninitialized]
foo.c:7:2: warning: 'c' is used uninitialized in this function [-Wuninitialized]
foo.c:9:6: warning: 'x' is used uninitialized in this function [-Wuninitialized]
  if(a%x==0 && b%x==0 && c%x==0)
     ~^~

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