foo.c: In function 'main':
foo.c:23:8: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   23 |     if(b=1)
      |        ^
foo.c:4:12: warning: variable 'a' set but not used [-Wunused-but-set-variable]
    4 |  int i,b,x,a;
      |            ^
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    5 |  scanf("%d",&x);
      |  ^~~~~~~~~~~~~~

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