吴裕雄--天生自然C语言开发：递归

void recursion()
{
   statements;
   ... ... ...
   recursion(); /* 函数调用自身 */
   ... ... ...
}

int main()
{
   recursion();
}

#include <stdio.h>

double factorial(unsigned int i)
{
   if(i <= )
   {
      return ;
   }
   return i * factorial(i - );
}
int  main()
{
    int i = ;
    printf("%d 的阶乘为 %f\n", i, factorial(i));
    return ;
}

#include <stdio.h>

int fibonaci(int i)
{
   if(i == )
   {
      return ;
   }
   if(i == )
   {
      return ;
   }
   return fibonaci(i-) + fibonaci(i-);
}

int  main()
{
    int i;
    for (i = ; i < ; i++)
    {
       printf("%d\t\n", fibonaci(i));
    }
    return ;
}

#include <stdio.h>
#include <stdarg.h>

double average(int num,...)
{

    va_list valist;
    double sum = 0.0;
    int i;

    /* 为 num 个参数初始化 valist */
    va_start(valist, num);

    /* 访问所有赋给 valist 的参数 */
    for (i = ; i < num; i++)
    {
       sum += va_arg(valist, int);
    }
    /* 清理为 valist 保留的内存 */
    va_end(valist);

    return sum/num;
}

int main()
{
   printf("Average of 2, 3, 4, 5 = %f\n", average(, ,,,));
   printf("Average of 5, 10, 15 = %f\n", average(, ,,));
}