C和Python中递归函数的不同输出

Question

我有一个用C和Python实现的drawPyramid_recursive函数。他们的逻辑是一样的。然而，它们的输出是不同的。为什么会这样？C和Python递归的函数调用堆栈中是否存在差异

---

C版本：

#include <stdio.h>

void drawPyramid_recursive(int height, int level)
{
    if (level == 0) // base case
    {
        return;
    }
    
    return drawPyramid_recursive(height, level - 1);

    for (int column = height - level; column >= 1; --column)
    {
        printf(" ");
    }

    for (int column = 1; column <= level; ++column)
    {
        printf("#");
    }

    printf("  ");

    for (int column = 1; column <= level; ++column)
    {
        printf("#");
    }

    printf("\n");
}

int main(void)
{
    int height;
    do
    {
        printf("Height: ");
        scanf("%i", &height);
    }
    while (height > 8 || height < 1);

    drawPyramid_recursive(height, height);
}

C版本的输出：

Height: 3
  #  #
 ##  ##
###  ###

---

Python版本：

def drawPyramid_recursive(height, level):
    if (level == 0):  # base case
        return

    drawPyramid_recursive(height, level - 1)

    for level in range(1, height + 1):
        for column in range(height - level, 0, -1):
            print(" ", end="")

        for column in range(1, level + 1):
            print("#", end="")

        print("  ", end="")

        for column in range(1, level + 1):
            print("#", end="")

        print()


def main():
    while True:
        height = input("Height: ")
        height = int(height)
        if (height >= 1 and height <= 8):
            break

    drawPyramid_recursive(height, height)


if __name__ == "__main__":
    main()

Python版本的输出：

Height: 3
  #  #
 ##  ##
###  ###
  #  #
 ##  ##
###  ###
  #  #
 ##  ##
###  ###

Answer 1

两件事：

第一:

The logic is the same among them.

不，逻辑是不同的。请再看一看Python代码中的for level in range(1, height + 1):行，它没有出现在C代码中

第二：
您可能应该去掉C代码中return drawPyramid_recursive(height, level - 1);行开头的关键字return。否则您将无法打印任何#。。。请参见此处：https://godbolt.org/z/TYYvWzqKb

Answer 2

在Python代码中，有以下代码：

for level in range(1, height + 1):
    for column in range(height - level, 0, -1):
        print(" ", end="")

但是在你的C代码中，没有任何等价物

考虑在C代码中添加：

for(int level = 1; level <= height; ++level)
{
    for(int column = height - level; column >= 0;  column)
    { 
        printf(" ");
    }
}

另外，在C版本中，您return drawPyramid_recursive(height, level - 1);但在Python版本中没有返回：drawPyramid_recursive(height, level - 1)您应该删除return，并将C代码更改为：drawPyramid_recursive(height, level - 1);