foo.c: In function 'main':
foo.c:5:2: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
    5 |  scanf("%d", &n);
      |  ^~~~~
foo.c:5:2: warning: incompatible implicit declaration of built-in function 'scanf'
foo.c:1:1: note: include '<stdio.h>' or provide a declaration of 'scanf'
  +++ |+#include <stdio.h>
    1 | int fibo(int x);
foo.c:10:3: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
   10 |   printf("%d ", fibo(a[i]))   ;
      |   ^~~~~~
foo.c:10:3: warning: incompatible implicit declaration of built-in function 'printf'
foo.c:10:3: note: include '<stdio.h>' or provide a declaration of 'printf'
foo.c:10:3: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
   10 |   printf("%d ", fibo(a[i]))   ;
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~
foo.c: In function 'fibo':
foo.c:26:9: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
   26 |  return c;
      |         ^

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