foo.c: In function 'main':
foo.c:9:27: error: expected ';' before '\U0000ff1b'
    9 | scanf("%d %d",&a[i],&b[i])；
      |                           ^~
      |                           ;
foo.c:20:7: warning: implicit declaration of function 'abs' [-Wimplicit-function-declaration]
   20 | len1+=abs(x-a[i])+abs(y-b[i]);
      |       ^~~
foo.c:3:1: note: include '<stdlib.h>' or provide a declaration of 'abs'
    2 | #include <math.h>
  +++ |+#include <stdlib.h>
    3 | int main()

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