foo.c: In function 'F':
foo.c:5:4: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
    5 |  if(m>n)
      |    ^
foo.c:4:9: warning: unused variable 'k' [-Wunused-variable]
    4 |     int k,i;
      |         ^
foo.c:13:1: warning: control reaches end of non-void function [-Wreturn-type]
   13 | }
      | ^
foo.c: In function 'main':
foo.c:17:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   17 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:19:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   19 |   scanf("%d %d",&b[i],&a[i]);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~

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