Grade Calculator in JavaScript

1// Grade system:
2// 90-100: A
3// 80-89: B
4// 70-79: C
5// 60-69: D
6// Below 60: F
7
8function calculateGrade(marks) {
9    if (marks >= 90 && marks <= 100) {
10        return 'A';
11    } else if (marks >= 80 && marks < 90) {
12        return 'B';
13    } else if (marks >= 70 && marks < 80) {
14        return 'C';
15    } else if (marks >= 60 && marks < 70) {
16        return 'D';
17    } else if (marks >= 0 && marks < 60) {
18        return 'F';
19    } else {
20        return 'Invalid marks';
21    }
22}
23
24// Test cases
25console.log("95 marks:", calculateGrade(95));
26console.log("85 marks:", calculateGrade(85));
27console.log("75 marks:", calculateGrade(75));
28console.log("65 marks:", calculateGrade(65));
29console.log("45 marks:", calculateGrade(45));
30console.log("105 marks:", calculateGrade(105));
31
32// Method 2: Using switch with ranges
33function calculateGrade2(marks) {
34    switch(true) {
35        case marks >= 90 && marks <= 100:
36            return 'A';
37        case marks >= 80 && marks < 90:
38            return 'B';
39        case marks >= 70 && marks < 80:
40            return 'C';
41        case marks >= 60 && marks < 70:
42            return 'D';
43        case marks >= 0 && marks < 60:
44            return 'F';
45        default:
46            return 'Invalid marks';
47    }
48}
49
50console.log("\nUsing switch:");
51console.log("92 marks:", calculateGrade2(92));
52console.log("78 marks:", calculateGrade2(78));