Suppose, we have an array of Number literals that contains some consecutive redundant entries like this −
const testArr = [1, 1, 2, 2, 3, 3, 1, 1, 1];
We are supposed to write a function compress that takes in this array and removes all redundant consecutive entries in place. So that the output looks like this −
const output = [1, 2, 3, 1];
Let’s write the code for this function, we will be using recursion for this and the code for this will be −
Example
const testArr = [1, 1, 2, 2, 3, 3, 1, 1, 1]; const compress = (arr, len = 0, canDelete = false) => { if(len < arr.length){ if(canDelete){ arr.splice(len, 1); len--; } return compress(arr, len+1, arr[len] === arr[len+1]) }; return; }; compress(testArr); console.log(testArr);
Output
The output in the console will be −
[ 1, 2, 3, 1 ]