foo.c: In function 'main':
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&m,&n);
  ^~~~~~~~~~~~~~~~~~~
foo.c:8:7: warning: 'i' is used uninitialized in this function [-Wuninitialized]
  while(i!=0)
       ^

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