foo.c:3:1: warning: return type defaults to 'int' [-Wimplicit-int]
    3 | max(int a[],int len)
      | ^~~
foo.c:17:1: warning: return type defaults to 'int' [-Wimplicit-int]
   17 | min(int a[],int len)
      | ^~~
foo.c: In function 'main':
foo.c:47:37: warning: implicit declaration of function 'abs' [-Wimplicit-function-declaration]
   47 |                                 d=d+abs(a[k]-i)+abs(b[k]-j);
      |                                     ^~~
foo.c:3:1: note: include '<stdlib.h>' or provide a declaration of 'abs'
    2 | #include<math.h>
  +++ |+#include <stdlib.h>
    3 | max(int a[],int len)

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