#include <stdio.h>
#include <math.h>

/* grade is a function that takes an integer argument
    and returns an integer */
int grade (int mark) {
    if (mark >= 90) {
        return 12;
    } else if (mark >= 85) {
        return 11;
    } else if (mark >= 80) {
        return 10;
    } else if (mark >= 77) {
        return 9;
    } else if (mark >= 73) {
        return 8;
    } else if (mark >= 70) {
        return 7;
    } else if (mark >= 67) {
        return 6;
    } else if (mark >= 63) {
        return 5;
    } else if (mark >= 60) {
        return 4;
    } else if (mark >= 57) {
        return 3;
    } else if (mark >= 53) {
        return 2;
    } else if (mark >= 50) {
        return 1;
    } else {
        return 0;
    }
}

int main() {
    int mark = 95;
    /* is it a problem that i have two int variables named mark? */

    printf("Enter a mark: ");
    scanf("%d", &mark);
    printf("a mark of %d would receive a grade of %d\n", mark, grade(mark));

    return 0;
}