Grade according to marks

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

int main() {
    int marks;

    printf("enter the marks?\n");
    scanf("%d",&marks);

    if (marks>=90){
        printf("A");
    }else if (marks>=80){
        printf("B");
    }else if (marks>=70){
        printf("C");
    }else if (marks>=60){
        printf("D");
    }else if (marks<60){
        printf("fail");
    }

    return 0;
}