javascript sum two numbers code example

Example 1: how to add two numbers in javascript

let a = 4;
let b = 5;
document.write(a + b);

Example 2: javascript function to add two numbers

<!--Add two integer numbers using JavaScript.-->
<html>
	<head>
		<title>Add two integer numbers using JavaScript.</title>
		<script type="text/javascript">
			function addTwoNumbers(textBox1, textBox2){
				var x=document.getElementById(textBox1).value;
				var y=document.getElementById(textBox2).value;
				var sum=0;
				sum=Number(x)+Number(y);
				alert("SUM is: " + sum);
			}
		</script>
	</head>
<body>
	<h1>Add two integer numbers using JavaScript.</h1>
	<b>Enter first Number: </b><br>
	<input type="text" id="textIn1"/><br>
	<b>Enter second Number: </b><br>
	<input type="text" id="textIn2"/><br><br>
	<input type="button" id="btnSum" value="Calculate SUM" onClick="addTwoNumbers('textIn1','textIn2')"/>
</body>

</html>

Example 3: two sum javascript

var twoSum = function(nums, target) {
    //hash table
    var hash = {};

    for(let i=0; i<=nums.length; i++){
      //current number
        var currentNumber = nums[i];
        //difference in the target and current number
        var requiredNumber = target - currentNumber;
        // find the difference number from hashTable
        const index2 = hash[requiredNumber];

        // if number found, return index 
        // it will return undefined if not found
        if(index2 != undefined) {
            return [index2, i]
        } else {
           // if not number found, we add the number into the hashTable
            hash[currentNumber] = i;

        }
    }
};

Example 4: add two numbers javascript

var x = 2 + 3;
//x = 5