c - 我的排序程序出错

Question

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



struct student{
    char initials[2];
    int score;
};

void sort(struct student* students, int n){
     /*Sort the n students based on their initials*/ 
           int i, j, replace;

     for(i = 0; i < n; i++)
     {
        for(j = 0; j < n; j++)
        {
            if(students[j] > students[j+1])
            {
                replace = students[j];
                students[j] = students[j+1];
                students[j+1] = replace;
            }
        }
     }
}

int main(){
    /*Declare an integer n and assign it a value.*/
    int n=10;

    /*Allocate memory for n students using malloc.*/
    struct student* students = (struct student *)malloc(n*sizeof(struct student));

    /*Generate random IDs and scores for the n students, using rand().*/
    int i;
    for(i=0; i<10; i++){
    (students + i)->initials[1] = rand( ) % 26 + 'A';
    (students + i)->initials[2] = rand( ) % 26 + 'A';
    }

    /*Print the contents of the array of n students.*/
    for(i=0; i<10; i++){         
    printf("%c%c\n", students[i].initials[1], students[i].initials[2]);
    }

    /*Pass this array along with n to the sort() function*/
    sort(students, n);

    /*Print the contents of the array of n students.*/


    return 0;
}

编译此代码时出现以下错误，

Program5.c: In function ‘sort’:

Program5.c:23:23: error: invalid operands to binary > (have ‘struct student’ and ‘struct student’)
        if(students[j] > students[j+1])
                       ^

Program5.c:25:17: error: invalid operands to binary == (have ‘int’ and ‘struct student’)
         replace == students[j];
                 ^

Program5.c:27:23: error: incompatible types when assigning to type ‘struct student’ from type ‘int’
         students[j+1] = replace;

任何帮助将不胜感激:)

Answer 1

前两个错误意味着编译器找不到 >(大于)运算符或 ==(等于)运算符来比较 学生到学生。编译器不能随便编造一个。您需要编写自己的 > 和 == 运算符。

第三个错误意味着编译器找不到接受 student 并将其分配给 int 的赋值运算符 (=) 。同样，您需要编写该运算符，因为编译器不知道您想要发生什么。

您应该能够通过搜索“define c++ == operator”或“define c++赋值运算符”等内容来找到定义这些运算符的正确语法。