foo.c: In function 'main':
foo.c:20:10: warning: too many arguments for format [-Wformat-extra-args]
   printf("yes\n",n); 
          ^~~~~~~
foo.c:24:10: warning: too many arguments for format [-Wformat-extra-args]
   printf("no\n",n); 
          ^~~~~~
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ^~~~~~~~~~~~~~

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