How do you do a chain of if statements in C?

Question

if (grade >= 75) {
    printf("\nPASSING");
    getch();
    goto Sol;

    if (grade >= 90) {
        printf("\nWITH HONORS");
        getch();
        goto Sol;

        if (grade >= 95) {
            printf("\nWITH HIGH HONORS");
            getch();
            goto Sol;

            if (grade >= 98) {
                printf("\nWITH HIGHEST HONORS");
                getch();
                goto Sol;

                if (grade >= 101) {
                    printf("INVALID");
                    getch();
                    goto Sol;
                }
            }
        }
    }
    else {
        printf("FAILURE");
        getch();
        goto Sol;
    }

This is my code so far but it won't work. What should I do to make it work?

Answer 1

There are multiple problems in your current code:

• you use goto, which is unnecessary and considered bad practice in most cases.

• the tests are in an incorrect order as every score greater or equal to 75 will be reported as PASSED but will not be tested for greater praise.

• also improve consistency in the newline usage.

Here is a modified version:

printf("\nGRADUATION STATUS: ");
if (grade >= 101) {
    printf("INVALID\n");
} else
if (grade >= 98) {
    printf("PASSING WITH HIGHEST HONORS\n");
} else
if (grade >= 95) {
    printf("PASSING WITH HIGH HONORS\n");
} else
if (grade >= 90) {
    printf("PASSING WITH HONORS\n");
} else
if (grade >= 75) {
    printf("PASSING\n");
} else {
    printf("FAILURE\n");
}
getch();

Answer 2

I believe you are looking for the following solution:

if ( grade >= 101 ) {
    printf( "INVALID\n" );
}
else if ( grade >= 75 ) {
    printf( "PASSING" );
    if ( grade >= 98 ) {
        printf( " WITH HIGHEST HONORS" );
    }
    else if ( grade >= 95 ) {
        printf( " WITH HIGH HONORS" );
    }
    else if ( grade >= 90 ) {
        printf( " WITH HONORS" );
    }
    printf( "\n" );
}
else {
    printf( "FAILURE\n" );
}
getch();

Note that it is normal to output \n at the end of the output, not at the start.

There is no need to call the function getch once in every code branch. It is sufficient to call it once at the end.

It is also worth pointing out that when learning programming, you should generally try to avoid the use of goto, as its use is considered bad practice in most situations. There are only a few cases in which the use of goto is considered appropriate. See the following links for further information: 1 2 3

Answer 3

I think you want the output to be:

    either
        PASSING
        (WITH HONORS or WITH HIGH HONORS or WITH HIGHEST HONORS)

    or
        FAILURE (for when grade is lower than 75)

    or
        INVALID

Now pay attention to the branching. You have total 3 main branch here. 1 is when the grade is above 75 2 is when the grade is below 75 3 is when the grade is either less than 0 or greater than 100

each of these branches define 1 if case. The branch 1 can further be broken down like this:

    if grade >= 75 PASSING
        if grade >= 98 WITH HIGHEST HONORS
        else if grade >= 95 WITH HIGH HONORS
        else if grade >= 90 WITH HONORS

This should be how you structure the if-else block.

Also a note about goto, it's a bad practice, generally you can achieve the same results using a loop with break statement

Answer 4

There are few things here you could do to improve the clarity of the code. First, goto statements are not really what you want to be using in this situation (see comments to your question). Secondly, the logic in your code is broken.

If you want to use if statements, consider adding else if that will change how the branches of the program are traversed; to make things work, you will also need to change the boundaries that you use for different "grades":

if (grade >= 75 && grade < 90) {
    printf("\nPASSING");
} else if (grade >= 90 && grade < 95) {
   printf("\nWITH HONORS");
} else if (grade >=95 && grade < 98) {
   printf("\nWITH HIGH HONORS");
} else if (grade >= 98 && grade <= 100) {  // note <= 100 rather than < 101, since 100 is still a valid grade
   printf("\nWITH HIGHEST HONORS");
} else if (grade > 100) { // again, most likely you want to treat anything above 100 as invalid
   printf("INVALID");
} else {
   printf("FAILURE");
}
getch();

Finally, you might want to encapsulate these statements within a function and return the value, as opposed to printing it directly. This will help you navigate the code later on, without having to ever think about goto statements.