 # JavaScript: Generates all combinations of a string

## JavaScript Function: Exercise-3 with Solution

Write a JavaScript function that generates all combinations of a string.
Example string: 'dog'
Expected Output: d,o,do,g,dg,og,dog

Pictorial Presentation: Sample Solution: -

HTML Code:

``````<!DOCTYPE html>
<html>
<meta charset=utf-8 />
<title>Combination of a string</title>
<body>

</body>
</html>
```
```

JavaScript Code:

``````//Write a JavaScript function that generates all combinations of a string.
function substrings(str1)
{
var array1 = [];
for (var x = 0, y=1; x < str1.length; x++,y++)
{
array1[x]=str1.substring(x, y);
}
var combi = [];
var temp= "";
var slent = Math.pow(2, array1.length);

for (var i = 0; i < slent ; i++)
{
temp= "";
for (var j=0;j<array1.length;j++) {
if ((i & Math.pow(2,j))){
temp += array1[j];
}
}
if (temp !== "")
{
combi.push(temp);
}
}
console.log(combi.join("\n"));
}

substrings("dog");
```
```

Sample Output:

```d
o
do
g
dg
og
dog
```

Flowchart: Live Demo:

See the Pen JavaScript -Check whether a passed string is palindrome or not-function-ex- 2 by w3resource (@w3resource) on CodePen.

Improve this sample solution and post your code through Disqus

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﻿

## JavaScript: Tips of the Day

Array of nested arrays

```const person = {
name: 'Owen',
age: 23,
};

for (const [x, y] of Object.entries(person)) {
console.log(x, y);
}
```

Object.entries(person) returns an array of nested arrays, containing the keys and objects:
[ [ 'name', 'Owen' ], [ 'age', 23 ] ] Using the for-of loop, we can iterate over each element in the array, the subarrays in this case. We can destructure the subarrays instantly in the for-of loop, using const [x, y]. x is equal to the first element in the subarray, y is equal to the second element in the subarray.
The first subarray is [ "name", "Owen" ], with x equal to "name", and y equal to "Owen", which get logged. The second subarray is [ "age", 23 ], with x equal to "age", and y equal to 23, which get logged.

Ref: https://bit.ly/3jFRBje