c语言递归调用题，刚刚起步不太懂。

Question

c语言读程序题，正确答案是c，为啥输出从0开始啊，会的博主可以教教我吗。

Answer 1

递进的顺序：n = 5  ==> fun(n-1)
        ==> n = 4 ==> fun(n-1)
        ==> n = 3 ==>fun(n-1)
        ==> n = 2 ==> fun(n-1)
        ==> n = 1 ==> fun(n-1)
        ==> n = 0
回归的顺序：
        0 <== printf("%d",n) <== n=0   <==
        1 <== printf("%d",n) <== n = 1 <==
        2 <== printf("%d",n) <== n = 2 <==
        3 <== printf("%d",n) <== n = 3 <==
        4 <== printf("%d",n) <== n = 4 <==
        5 <== printf("%d",n) <== n = 5 <==