foo.c: In function 'main':
foo.c:12:10: warning: unused variable 'nc' [-Wunused-variable]
  int y=1,nc;
          ^~
foo.c:11:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d",&x,&n,&k);
  ^~~~~~~~~~~~~~~~~~~~~~~~
foo.c: In function 'Mul':
foo.c:41:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

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