函数返回类型赋值给一个指针却报错？(语言-c语言)

Question

各位能看看嘛？
我把返回结果(指针类型）赋值给相同类型的一个指针，报错显示：应输入表达式

```c
#define _CRT_SECURE_NO_WARNINGS

#include<stdio.h>
#include<string.h>

typedef struct function
{
    char* func_name;
    void (*func_pointer)(void);


}function_list;

int add(int a, int b);
int add(int a, int b) {
    return a + b;
}



int compare(int a, int b);
int compare(int a, int b);
int compare(int a, int b) {
    return a > b ? a : b;
}


int equal(int a, int b);
int equal(int a, int b) {
    if (a == b)
        return 1;
    else 0;
}




int *find(char u, function_list *a) {
    
    while (strcmp(a->func_name,u)!=0)
    {
        *a++;

    }
    if (strcmp(a->func_name, u) != 0)
    {
        printf("未找到相关函数");
        return 0;
    }
    else
    {
        return a->func_pointer;
    }
    

}
int main() {
    
    int(*p)(int, int);
    p = add;
    int (*q)(int, int);
    q = compare;
    int(*r)(int, int);
    r = equal;

    function_list a[] = {
    {"add",*p},
    {"compare",*q},
    {"equal",*r}

    };


    char t;
    printf("input function name that you want:\n");
    scanf("%s", &t);
    int* i = find(t, a);
    


}

Answer 1

结构体 function_list 是怎么定义的？是否是这么改，供参考：

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <string.h>
typedef struct function
{
    char* func_name;
    int (*func_pointer)(int, int);   //修改
}function_list;

int add(int a, int b);
int add(int a, int b) {
    return a + b;
}

int compare(int a, int b);
int compare(int a, int b) {
    return a > b ? a : b;
}

int equal(int a, int b);
int equal(int a, int b) {
    if (a == b)
        return 1;
    else 
        return 0; //修改
}

int find(char* u, function_list* a, int n, int b, int c) //修改
{
    for (int i = 0; i < n; i++) {                  //修改
        if (strcmp((a + i)->func_name, u) == 0)    //修改
            return (a + i)->func_pointer(b, c);    //修改
    }
    return 0;
}

int main() 
{
    int n = 3;
    //int(*p)(int, int);  //修改
    //p = add;
    //int (*q)(int, int);
    //q = compare;
    //int(*r)(int, int);
    //r = equal;
    function_list a[3] = {                   //修改
                         {"add",add},        //修改
                         {"compare",compare},//修改
                         {"equal",equal}     //修改
    };
    char t[16];      //修改
    printf("input function name that you want:\n");
    scanf("%s", t);  //scanf("%s", &t); //修改
    int i = find(t, a, n, 5, 5);        //修改
    printf("%d", i);
    return 0;
}