小编Tri*_*lla的帖子

In one of my course's tutorial videos, I have encountered a situation where pass by value and pass by reference is occurring. In the example he gives us, he, firstly, admits that the code is written poorly, and then asks us to find out what exactly would be printed. The relevant code is as follows:

void set_array(int array[4]);
void set_int(int x);

int main(void){
    int a = 10; 
    int b[4] = {0, 1, 2, 3);
    set_int(a);
    set_array(b);
    printf("%d %d\n", a, b[0]); …

在 code::blocks 中编写以下代码时，在 main 中调用时不会产生所需的结果：

#include <stdio.h>
#include <stdlib.h>

float mult_two_floats(float a, float b);
int main()
{
    mult_two_floats(7,7);
    return 0;
}
float mult_two_floats(float a, float b){
    return a * b;
}

当重写如下时，它确实有效：

#include <stdio.h>
#include <stdlib.h>


float mult_two_floats(float a, float b);
int main()
{
    mult_two_floats(7,8);
    return 0;
}
float mult_two_floats(float a, float b){
    printf("%f", a*b);
}

请帮助我了解我做错了什么。谢谢你。