Question

C语言调用函数指针

图1是我自己写的代码。
图2是老师的代码。
程序是为了实现指针变量值能按大小输出。
对比了老师的代码，发现自己好像写的不是很规范，也好像不对的样子…请问大佬们…这样书写可以吗？





Answer 1

这道编程，关键价值，体现传址对实参的影响。

你的写法不算错，只是函数写错了。

--你函数调用那里，传的参数是指针型也就是地址（zhizhe(*arr,*brr);)。

--而你函数定义和申明，参数都是int型，类型不匹配。

你和老师最大的区别：

--你的写法打印输出是写在调用函数内的，用的是函数的局部变量，体现不出传址的作用。

--老师的写法打印是在调用之后主函数中打印的，用的是实参，可以清楚看出，传址到函数，值改变后，实参值也改变。

另外你和老师写的函数作用也不一样：

--你的写法,比较大小是在子函数内部，那么子函数就具有比较功能。

--老师写法，比较写在主函数中，子函数只是单纯交换。

Answer 2

#include <stdio.h>                                                                   
                                                                                     
// 函数声明一般放main上面                                                               
void zhizhen(int a, int b);                                                          
void swap(int *a, int *b);                                                           
                                                                                     
int main(void) {                                                                        
    int a, b;                                                                           
    printf("input a value\n");                                                          
    scanf("%d", &a);                                                                    
    printf("input b value\n");                                                          
    scanf("%d", &b);                                                                    
    printf("a==>%d\t>\tb==>%d\n", a, b);                                                
    zhizhen(a, b); //´«Öµ                                                               
    printf("a==>%d\t>\tb==>%d\n", a, b);                                                
                                                                                        
    swap(&a, &b);// ´«µØÖ·                                                              
    printf("a==>%d\t>\tb==>%d\n", a, b);                                                
                                                                                        
    return 0;                                                                           
}                                                                                                                                                                           
                                                                                        
// 传递指针,通过指针修改a和b的值                                                        
void swap(int *a, int *b) {                                                             
    int temp;                                                                           
    if (*a > *b) {                                                                      
        temp = *a;                                                                      
        *a = *b;                                                                        
        *b = temp;                                                                      
    }                                                                                
    /*printf("b==> %d\t>\ta==>%d\n", *b, *a);*/                                      
}                                                                                    
                                                                                     
// 值传递                                                                            
void zhizhen(int a, int b) {                                                            
    int temp;
     if (a > b) {                                                                     
        temp = a;                                                                    
        a = b;                                                                                                                                                              
        b = temp;                                                                    
    }                                                                                
                                                                                     
    /*printf("b==>%d\t>\ta==>%d\n", b, a);*/                                         
}

给你注释了！

Answer 3

你们的函数有着质的区别。
你可以想象内存是宾馆，有很多房间。指针是门牌号码，一个指针指向一间房间。
你的函数是在宾馆外另外建了两座新房间，操作一通然后回到宾馆对于宾馆内部无任何改动。
老师的函数是把两间房间的门牌号换了，门牌A放到了原先门牌B指向的房间门口，这样房间不用动，只是换门牌，省下了很多资源和操作。

Answer 4

墨兰公主
付出了也许没有结果，
但不付出一定不会有结果。
一个人如果没有成功，
要么智慧不够，要么付出不够，
练多了就熟了，学多了就会了。
没有天赋可以用勤奋来弥补！
——早安！[太阳][太阳]

Answer 5

好绝望，怎么都学不会，能指点指点下吗