c - C 中的 else if 语句未按预期工作

Question

我的程序在下面，我试图在 visual studio 上运行它，但它一直给我一个错误 Illegal if Without matching if。

我相信它试图告诉我我的 else 与我的 if 不匹配，但它确实匹配。以下是我的代码；有人可以运行它并让我知道问题出在哪里，这样我以后就不会重复了吗？

/* counting number of students that pass*/
#include <stdio.h>

main()
{
    int pass, fail, grade;
    printf(" This program  tells you total number of students that passed\n Enter -1 to finish the program");

    pass = 0;
    fail = 0;
    grade = 0;

    while (grade != -1) {           /* Enter -1 to finish the while loop*/
        printf("Enter the grade of the student, 1 is pass, 2 is fail, -1 finishes the program\n");
        scanf_s("%d", &grade);
        if (grade == 1)
            printf("The student passed\n");
        pass = pass + 1;                /* Add 1 to the pass*/
        else if (grade == 2)
            printf("The student failed\n");
        fail = fail + 1;            /*Add 1 to fail */
        else
            printf("You have entered an invalid number, please try again\n");
    }

    if (pass > 8)
        printf("More than 8 students passed; raise tuition fees\n");

    getchar();
}

Answer 1

大括号是你的 friend 。更改代码段

if (grade == 1)
    printf("The student passed\n");
pass = pass + 1;                /* Add 1 to the pass*/
else if (grade == 2)
    printf("The student failed\n");
fail = fail + 1; 

到

if (grade == 1){
    printf("The student passed\n");
    pass = pass + 1;                /* Add 1 to the pass*/
}
else if (grade == 2){
    printf("The student failed\n");
    fail = fail + 1;
}