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Get n numbers from array starting from given point JavaScript
We have to write an array function (Array.prototype.get()) that takes in three arguments first, a number n, second is also a number, say m, (m <= array length-1) and second is a string that can have one of the two values − ‘left’ or ‘right’.
The function should return a subarray of the original array that should contain n elements starting from the index m, and in the specified direction like left or right.
For example −
// if the array is: const arr = [0, 1, 2, 3, 4, 5, 6, 7]; // and the function call is: arr.get(4, 6, 'right'); // then the output should be: const output = [6, 7, 0, 1];
So, let’s write the code for this function −
Example
const arr = [0, 1, 2, 3, 4, 5, 6, 7];
Array.prototype.get = function(num, ind, direction){
const amount = direction === 'left' ? -1 : 1;
if(ind > this.length-1){
return false;
};
const res = [];
for(let i = ind, j = 0; j < num; i += amount, j++){
if(i > this.length-1){
i = i % this.length;
};
if(i < 0){
i = this.length-1;
};
res.push(this[i]);
};
return res;
};
console.log(arr.get(4, 6, 'right'));
console.log(arr.get(9, 6, 'left'));
Output
The output in the console will be −
[ 6, 7, 0, 1 ] [ 6, 5, 4, 3, 2, 1, 0, 7, 6 ]
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