利用可变参数打印出递归函数的树形输出

 1 #include <cstdio>
 2 
 3 #define Log(level, fmt, ...) do{if(true)  4     {for(int i = 0; i < level - 1; i++) printf("--");             5 printf(fmt"\n", ##__VA_ARGS__);} }while(false)
 6 
 7 unsigned fibonacci(unsigned n, int level)
 8 {
 9     Log(level, "fibonacci(%d)", n);
10     if(n < 2)
11         return n;
12     else 
13         return fibonacci(n - 1, level + 1) + fibonacci(n - 2, level + 1);
14 }
15 
16 int main()
17 {
18     fibonacci(6, 1);
19     return 0;
20 }