foo.c: In function 'bei':
foo.c:28:6: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   28 |   if(t=a)
      |      ^
foo.c:34:11: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   34 |   else if(t=b)
      |           ^
foo.c:25:10: warning: variable 'y' set but not used [-Wunused-but-set-variable]
   25 |  int s,x,y;
      |          ^
foo.c:25:8: warning: variable 'x' set but not used [-Wunused-but-set-variable]
   25 |  int s,x,y;
      |        ^
foo.c: In function 'main':
foo.c:53:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   53 |  scanf("%d %d\n%d %d",&b1,&a1,&b2,&a2);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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