foo.c: In function 'main':
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&n1,&n2);
  ^~~~~~~~~~~~~~~~~~~~~~
foo.c:22:15: warning: 'd' may be used uninitialized in this function [-Wmaybe-uninitialized]
  printf("%d",d-c+p);
              ~^~
foo.c:22:2: warning: 'p' may be used uninitialized in this function [-Wmaybe-uninitialized]
  printf("%d",d-c+p);
  ^~~~~~~~~~~~~~~~~~
foo.c:22:15: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
  printf("%d",d-c+p);
              ~^~

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