foo.c: In function 'main':
foo.c:11:25: warning: implicit declaration of function 'output'; did you mean 'Output'? [-Wimplicit-function-declaration]
   11 |  if(n<10000){input(a,n);output(a,n);}}
      |                         ^~~~~~
      |                         Output
foo.c: In function 'input':
foo.c:4:18: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    4 |  for(i=0;i<n;i++)scanf("%d ",&a[i]);}
      |                  ^~~~~~~~~~~~~~~~~~
foo.c: In function 'main':
foo.c:10:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   10 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
/usr/bin/ld: /tmp/cc7a7NSs.o: in function `main':
foo.c:(.text.startup+0x98): undefined reference to `output'
collect2: error: ld returned 1 exit status

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