JavaScript Programs
1.Write JavaScript code to print subtraction of 2 numbers.
<html>
<head>
<title>JS program to subtract two numbers</title>
</head>
<body>
<script>
var n1, n2, diff;
n1=parseInt(prompt("Enter first number:"));
n2=parseInt(prompt("Enter second number:"));
diff=n2-n1;
alert("Subtraction - " + diff);
</script>
</body>
</html>
2.Write JavaScript code to print addition of 2 numbers.
<html>
<head>
<title>JS program to add two numbers</title>
</head>
<body>
<script>
var n1, n2, sum;
n1=parseInt(prompt("Enter first number:"));
n2=parseInt(prompt("Enter second number:"));
sum=n1+n2;
alert("Sum- " + sum);
</script>
</body>
</html>
3.Write JavaScript code to print multiplication of 2 numbers.
<html>
<head>
<title>JS program to multiply two numbers</title>
</head>
<body>
<script>
var n1, n2, prod;
n1=parseInt(prompt("Enter first number:"));
n2=parseInt(prompt("Enter second number:"));
prod=n1*n2;
alert("Product - " + prod);
</script>
</body>
</html>
4.Write JavaScript code to print division of 2 numbers.
<html>
<head>
<title>JS program to divide two numbers</title>
</head>
<body>
<script>
var n1, n2, q;
n1=parseInt(prompt("Enter first number:"));
n2=parseInt(prompt("Enter second number:"));
q=n1/n2;
alert("Division - " + q);
</script>
</body>
</html>
5.Write JavaScript code to print addition, subtraction, multiplication & division of 2 numbers.
<html>
<head>
<title>JS program to add, subtract, multiply, divide two numbers</title>
</head>
<body>
<script>
var n1, n2, s,d,m,q;
n1=parseInt(prompt("Enter first number:"));
n2=parseInt(prompt("Enter second number:"));
s=n1+n2;
d=n2-n1;
m=n1*n2;
q=n1/n2;
document.write("<br>Sum - " + s);
document.write("<br>Difference - " + d);
document.write("<br>Product - " + m);
document.write("<br>Division - " + q);
</script>
</body>
</html>
6.Write JavaScript code to display area of circle, accept value from user.
7.Write JavaScript code to print area of triangle.
<html>
<head>
<title>JS program to calculate area of circle</title>
</head>
<body>
<script>
var r, area;
r=parseInt(prompt("Enter radius of the circle:"));
area=3.14*r*r;
alert("Area - " + area);
</script>
</body>
</html>
8.Write JavaScript code to calculate the average of three numbers.
<html>
<head>
<title>JS program to calculate average of three numbers</title>
</head>
<body>
<script>
var n1, n2, n3 avg;
n1=parseInt(prompt("Enter first number:"));
n2=parseInt(prompt("Enter second number:"));
n3=parseInt(prompt("Enter third number:"));
avg=(n1+n2+n3)/3;
alert("Average - " + avg);
</script>
</body>
</html>
9.Write JavaScript code to print perimeter of rectangle.
<html>
<head>
<title>JS program to calculate perimeter of rectangle</title>
</head>
<body>
<script>
var length, breadth, p;
length=parseInt(prompt("Enter length of the rectangle:"));
breadth=parseInt(prompt("Enter breadth of the rectangle:"));
p=2*(length+breadth);
alert("Perimeter- " + p);
</script>
</body>
</html>
10.Write JavaScript code to print perimeter of trapezium.
<html>
<head>
<title>JS program to calculate perimeter of trapezium</title>
</head>
<body>
<script>
var a, b, c, d, p;
a=parseInt(prompt("Enter length of the first side of trapezium:"));
b=parseInt(prompt("Enter length of the second side of trapezium:"));
c=parseInt(prompt("Enter length of the third side of trapezium:"));
d=parseInt(prompt("Enter length of the fourth side of trapezium:"));
p=a+b+c+d;
alert("Perimeter - " + p);
</script>
</body>
</html>
11.Write JavaScript code to check whether the number is odd or even.
<html>
<head>
<title>JS program to check number is odd or even</title>
</head>
<body>
<script>
var n;
n=parseInt(prompt("Enter a number:"));
if(n%2==0)
alert("Number is even");
else
alert("Number is odd");
</script>
</body>
</html>
12. Write JavaScript code to enter two values and display the largest.
<html>
<head>
<title>JS program to find largest number</title>
</head>
<body>
<script>
var n1, n2;
n1=parseInt(prompt("Enter first number:"));
n2=parseInt(prompt("Enter second number:"));
if(n1>n2)
alert("Larger number - " + n1);
else
alert("Larger number - " + n2);
</script>
</body>
</html>
13. Write JavaScript code to print multiplication table of 3.
<html>
<head>
<title>JS program to print multiplication table of 3</title>
</head>
<body>
<script>
var n=3, i;
document.write("Multiplication table of 3");
for(i=1;i<=10;i++)
{
document.write("<br>"+n+" * "+i+" = "+n*i);
}
</script>
</body>
</html>
14.Write JavaScript code to print numbers from 1 to 10.
<html>
<head>
<title>JS program to print numbers from 1 to 10</title>
</head>
<body>
<script>
var i;
document.write("Numbers from 1 to 10");
for(i=1;i<=10;i++)
{
document.write("<br>"+i);
}
</script>
</body>
</html>
15.Write JavaScript code to print sum of 50 natural numbers.
<html>
<head>
<title>JS program to print sum of 50 natural numbers.</title>
</head>
<body>
<script>
var i, sum=0;
document.write("Sum of numbers from 1 to 50");
for(i=1;i<=50;i++)
{
document.write("<br>"+i);
sum=sum+i;
}
document.write("<br>Sum - "+sum);
</script>
</body>
</html>
16.Write JavaScript code to print all even numbers from 10 to 50.
<html>
<head>
<title>JS program to print even numbers from 10 to 50</title>
</head>
<body>
<script>
var i;
document.write("Even Numbers from 10 to 50");
for(i=10;i<=50;i++)
{
if(i%2==0)
document.write("<br>"+i);
}
</script>
</body>
</html>
17.Write JavaScript code when user click on button, it will display sum of even numbers from 1 to 10.
<html>
<head>
<title>JS program to print sum of even numbers.</title>
<script>
function display_sum() {
var i, sum=0;
for(i=1;i<=10;i++)
{
if(i%2==0)
sum=sum+i;
}
document.getElementById("disp").innerHTML = "Sum of even numbers from 1to10 - " + sum;
}
</script>
</head>
<body>
<input type="button" name="disp_sum" value="Display Sum" onclick="display_sum()">
<br>
<p id="disp"> </p>
</body>
</html>
18.Write JavaScript code to print all odd numbers from 50 to 100.
<html>
<head>
<title>JS program </title>
</head>
<body>
<h1>JS program to print odd numbers from 50 to 100</h1>
<script>
var i;
document.write("Odd Numbers from 50 to 100");
for(i=50;i<=100;i++)
{
if(i%2!=0)
document.write("<br>"+i);
}
</script>
</body>
</html>
19.Write JavaScript code to print factorial of 7 on button click.
<html>
<head>
<title>JS program - factorial of number</title>
<script>
function display_factorial(num) {
var i, f = 1;
for (i = num; i >= 1; i--) {
f=f*i;
}
document.getElementById("disp").innerHTML = "Factorial of 7 - " + f;
}
</script>
</head>
<body>
<h1>JS program to print factorial of number</h1>
<input type="button" name="disp_fact" value="Display Factorial" onclick="display_factorial(7)">
<br>
<p id="disp"> </p>
</body>
</html>
20.Write JavaScript code to print square of a accepted number.
<html>
<head>
<title>JS program to display square of a number</title>
</head>
<body>
<script>
var n, r;
n=parseInt(prompt("Enter a number:"));
r=n*n
alert("Square - " + r);
</script>
</body>
</html>
21.Write JavaScript code to count length of accepted string after click on the button.
<html>
<head>
<title>JS program</title>
<script>
function display_length() {
var str, len;
str = form1.str_box.value;
len = str.length;
document.getElementById("disp").innerHTML = "Length of String - " + len;
}
</script>
</head>
<body>
<h1>JS program to print length of string</h1>
<form name="form1">
<input type="text" name="str_box" size=50>
<input type="button" name="disp_strlen" value="Display Length" onclick="display_length()">
</form>
<br>
<p id="disp"> </p>
</body>
</html>
22.Write JavaScript code to accept two dates and find the difference in those dates.
<html>
<head>
<title>JS program</title>
<script>
function display_diff() {
var d1, d2, diff;
d1 = new Date(form1.date1.value);
d2 = new Date(form1.date2.value);
diff = (d2 - d1) / (1000 * 3600 * 24);
document.getElementById("disp").innerHTML = "Difference of dates in days - " + diff;
}
</script>
</head>
<body>
<h1>JS program to display difference between dates</h1>
<form name="form1">
<input type="date" name="date1">
<br> <br>
<input type="date" name="date2">
<br> <br>
<input type="button" name="disp_diff" value="Display Difference" onclick="display_diff()">
</form>
<br>
<p id="disp"> </p>
</body>
</html>
23.Write JavaScript code to take a input of string and reverse the string in output.
<html>
<head>
<title>JS program - revverse of string</title>
<script>
function display_reverse(str) {
var newstr;
newstr = str.split("").reverse().join("")
document.write("Reverse of String - " + newstr);
}
</script>
</head>
<body>
<h1>JS program to reverse a string</h1>
<script>
var s;
s = prompt("Input a string");
display_reverse(s)
</script>
</body>
</html>
24.Write JavaScript code to input 3 digit number and find sum and product of its digit of the number use onblur event for the program.
25.Write JavaScript code to print factorial of accepted number.
