> For the complete documentation index, see [llms.txt](https://mentebinaria.gitbook.io/manual-da-linguagem-gnu-c/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://mentebinaria.gitbook.io/manual-da-linguagem-gnu-c/2.-um-programa-completo/exemplo-de-um-programa-completo.md).

# Exemplo de um Programa Completo

Aqui está um exemplo de um programa completo que usa uma versão simples, recursiva, da função `fib` (ver [Fibonacci Recursiva](/manual-da-linguagem-gnu-c/o-primeiro-exemplo/fibonacci-recursivo.md)):

```c
#include <stdio.h>

int
fib (int n)
{
  if (n <= 2)  /* Isto evita recursividade infinita. */
    return 1;
  else
    return fib (n - 1) + fib (n - 2);
}

int
main (void)
{
  printf ("O item %d da série de Fibonacci é %d\n",
          20, fib (20));
  return 0;
}
```

Este programa imprime uma mensagem que exibe o valor de `fib (20)`.

Agora vamos à uma explicação sobre este código.


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