foo.c: In function 'main':
foo.c:9:3: warning: statement with no effect [-Wunused-value]
  1<=a;0<=b<=2147483647;
  ~^~~
foo.c:9:11: warning: comparison of constant '2147483647' with boolean expression is always true [-Wbool-compare]
  1<=a;0<=b<=2147483647;
           ^~
foo.c:9:8: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
  1<=a;0<=b<=2147483647;
       ~^~~
foo.c:9:7: warning: statement with no effect [-Wunused-value]
  1<=a;0<=b<=2147483647;
       ^
foo.c:10:7: warning: statement with no effect [-Wunused-value]
  for(b!=0)
      ~^~~
foo.c:10:10: error: expected ';' before ')' token
  for(b!=0)
          ^
foo.c:10:10: error: expected expression before ')' token
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&a,&b);
  ^~~~~~~~~~~~~~~~~~~~

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