Nodejs Array Rotate rotateArray(n)

Method Source Code

/*//from   ww w.  j a v a  2  s .c o m
*   Rotate an array 
*   Input : 
*       [1, 2, 3, 4, 5, 6, 7, 8, 9]
*       3
*   Output :
*       [7, 8, 9, 1, 2, 3, 4, 5, 6]
*   -------------------------------
*   Input : 
*       [1, 2, 3, 4]
*       1
*   Output :
*       [4, 1, 2, 3]
*   -------------------------------
*   Input : 
*       [1, 2, 3, 4]
*       0
*   Output :
*       [1, 2, 3, 4]
*/

Array.prototype.rotateArray = function (n) {
    let firstArray = [];
    let secondArray = [];
    for (let i = this.length - 1; i > this.length - n - 1; i--) {
        firstArray.unshift(this[i]);
    }
    for (let j = 0; j < this.length - n; j++) {
        secondArray[secondArray.length] = this[j];
    }
    return firstArray.concat(secondArray);
}

function createArray() {
    let valuesStr = prompt("Enter an Array : ");
    let arrayStr = valuesStr.split(" ");
    let array = [];
    for (let i = 0; i < arrayStr.length; i++) {
        if (arrayStr[i] )
        array[array.length] = Number(arrayStr[i]);
    }
    return array;
}
 
let array = createArray();
console.log(array.rotateArray(3));

Related

1. rotate(K)

   Array.prototype.rotate = function (K){
     var N = this.length;
     if( N  < 1 || K < 1 || K > N ){
       return this;
     this.reverse(0, N - K - 1);
     this.reverse(N-K, N-1);
     this.reverse();
     return this;
   ...
   

2. rotate(count)

   Array.prototype.rotate = function(count)
           var len = this.length >>> 0, 
               count = count >> 0; 
           count = ((count % len) + len) % len;
           var copy = this.clone(this);
           push.apply(copy, splice.call(copy, 0, count));
           return copy;
     };
   ...
   

3. rotate(n)

   Array.prototype.rotate = function(n) {
     this.unshift.apply(this, this.splice(n + 1, this.length))
     return this;
   var arr = [1, 2, 3, 4, 5];
   var arr1 = [1, 2, 3, 4, 5];
   var rotate = function(arr, r) {
     arr.unshift.apply(arr, arr.splice(r + 1, arr.length));
   };
   ...
   

4. rotate(n)

   var a =  (function() { var a = []; for (var i = 0; i < 35; i++) { a.push(i) }; return a; }())
   Array.prototype.rotate = function(n) {
     var a = this.concat(this.splice(0, n))
     return a
   a.rotate(12)
   function findI(arr, i) {
     if (arr.length == 2) { return i+1 }
     var k = (arr.length/2).floor(), i = i || 0
   ...
   

5. rotate(times)

   Array.prototype.rotate = function(times) {
     if (times < 0) {
       var last = arr.pop
       return arr.unshift(last)
   function solution (numbers, times) {
     for (var i = 0; i < times; i++) {
       numbers.rotate
   ...
   

6. rotate_copy(begin, middle, end)

   Array.prototype.rotate_copy = function (begin, middle, end) {
     var back = this.slice (begin, middle - begin);
     back.unshift (0);
     back.unshift (end - middle);
     var front = this.slice (middle, end);
     front.splice.apply (front, back);
     return front;
   };