foo.c: In function 'main':
foo.c:13:28: warning: unused variable 'y' [-Wunused-variable]
   13 |  int b1,a1,b2,a2,m,n,i,j,x,y;
      |                            ^
foo.c:13:26: warning: unused variable 'x' [-Wunused-variable]
   13 |  int b1,a1,b2,a2,m,n,i,j,x,y;
      |                          ^
foo.c:13:24: warning: unused variable 'j' [-Wunused-variable]
   13 |  int b1,a1,b2,a2,m,n,i,j,x,y;
      |                        ^
foo.c:13:22: warning: unused variable 'i' [-Wunused-variable]
   13 |  int b1,a1,b2,a2,m,n,i,j,x,y;
      |                      ^
foo.c:16:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   16 |  scanf("%d %d",&b1,&a1);
      |  ^~~~~~~~~~~~~~~~~~~~~~
foo.c:17:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   17 |  scanf("%d %d",&b2,&a2);
      |  ^~~~~~~~~~~~~~~~~~~~~~

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