否则，如果C中的语句未按预期工作

Question

My program is below, i'm trying to run it on visual studio and it keeps giving me an error Illegal if Without matching if .

I believe it is trying to tell me that my else doesn't match my if , but it does. Below is my code; can someone run it and let me know what the problem is so I don't repeat it in the future?

/* 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

Braces are your friends. Change the snippet

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; 

to

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;
}

Answer 2

    if (grade == 1)
        printf("The student passed\n");
    pass = pass + 1; 

The code pass = pass + 1; is not under the if statement, you need braces for multiple statements:

if (grade == 1)
{
    printf("The student passed\n");
    pass = pass + 1; 
} 


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

Answer 3

The statement pass = pass +1; will be outside your if unless you use braces to define where your if starts and ends:

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