foo.c: In function 'main':
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
foo.c:8:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |   scanf("%d", &a[i]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c: In function 'fibo':
foo.c:17:20: warning: 'c' may be used uninitialized in this function [-Wmaybe-uninitialized]
   17 |  int a = 0, b = 1, c, i;
      |                    ^

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