Operators
let a = 10, b = 3;
console.log(a + b, a - b, a * b); // 13 7 30
console.log(a / b); // 3.333...
console.log(a % b); // 1 (remainder)
console.log(a ** 2); // 100 (power)
a += 5; // a = a + 5Comparison and logical operators
console.log(5 === 5, 5 !== 6); // true true
console.log(5 > 3, 5 <= 4); // true false
console.log(true && false); // false (AND)
console.log(true || false); // true (OR)
console.log(!true); // false (NOT)if, else if, else
<script>
const marks = 72;
let grade;
if (marks >= 90) {
grade = "A+";
} else if (marks >= 75) {
grade = "A";
} else if (marks >= 60) {
grade = "B";
} else {
grade = "Needs improvement";
}
document.write("Marks: " + marks + ", Grade: " + grade);
</script>switch
const day = "Sat";
switch (day) {
case "Sat":
case "Sun":
console.log("Weekend");
break;
default:
console.log("Weekday");
}Ternary operator
const status = marks >= 40 ? "Pass" : "Fail";Truthy and falsy
false, 0, "", null, undefined and NaN are falsy. Everything else is truthy.
const name = "";
console.log(name || "Guest"); // "Guest"Practice
Write a program that takes a number and prints whether it is positive, negative or zero, and whether it is even or odd.