Java > Array-2 > shiftLeft (CodingBat Solution)

Problem:

Return an array that is "left shifted" by one -- so {6, 2, 5, 3} returns {2, 5, 3, 6}. You may modify and return the given array, or return a new array.

shiftLeft({6, 2, 5, 3}) → {2, 5, 3, 6}
shiftLeft({1, 2}) → {2, 1}
shiftLeft({1}) → {1}


Solution:

public int[] shiftLeft(int[] nums) {  
  int[] foo;
  foo = new int[nums.length];
  
  if (nums.length == 0)
    return foo;
  
  for (int i = 0; i < nums.length-1; i++) {
    if (i > 0)
      foo[i] = nums[i+1];
  }
  if (nums.length > 1)
    foo[0] = nums[1];
  foo[nums.length-1] = nums[0];
  return foo;
}

12 comments:

  1. UnknownApril 9, 2017 at 8:30 AM

    public int[] shiftLeft(int[] nums) {
    int len = nums.length;
    int temp = 0;
    for(int i=0; i<len-1; i++){
    temp = nums[i];
    nums[i]= nums[i+1];
    nums[i+1] = temp;
    }
    return nums;
    }

    ReplyDelete
  2. fergcodyJanuary 7, 2019 at 11:58 AM

    public int[] shiftLeft(int[] nums) {
    int[] newArray;
    int lastNum;

    if(nums.length == 0) {
    return nums;
    } else {
    newArray = nums;
    lastNum = nums[0];

    for(int i = 0; i < nums.length - 1; i++) {
    newArray[i] = nums[i + 1];
    }
    newArray[newArray.length -1] = lastNum;
    }
    return newArray;
    }

    ReplyDelete
  3. IntercisaJune 17, 2019 at 7:59 AM

    public int[] shiftLeft(int[] nums) {
    if (nums.length <= 0) {
    return nums;
    }

    int[] array = new int[nums.length];

    int first = nums[0];

    for (int i = 0, j = 1; j < nums.length; i++, j++) {

    array[i] = nums[j];

    }
    array[array.length - 1] = first;

    return array;

    ReplyDelete
  4. KnownJune 23, 2019 at 4:46 AM

    public int[] shiftLeft(int[] nums) {
    if(nums.length <= 1) return nums;

    int tmp = nums[0];
    for(int i = 0; i < nums.length - 1; i++) {
    nums[i] = nums[i + 1];
    }
    nums[nums.length - 1] = tmp;
    return nums;
    }

    ReplyDelete
  5. UnknownOctober 30, 2019 at 9:35 AM

    public int[] shiftLeft(int[] nums)
    {
    int i,j;
    //int k=nums[0];
    int l=nums.length;
    int a[]=new int[l];
    if(l==0)
    {
    return a;
    }
    int k=nums[0];
    for(i=0;i<1;i++)
    {
    for(j=0;j<l-1;j++)
    {
    a[j]= nums[j+1];
    }
    a[j]=k;
    }
    return a;
    }

    ReplyDelete
  6. DIVRITMay 20, 2020 at 12:32 AM

    public int[] shiftLeft(int[] nums) {
    int temp=0;

    if(nums.length<1)
    return nums;

    temp=nums[0];
    for(int i=0;i<nums.length-1;i++){
    nums[i]=nums[i+1];
    }

    nums[nums.length-1]=temp;

    return nums;
    }

    ReplyDelete
  7. UnknownJuly 26, 2020 at 2:29 PM

    public int[] shiftLeft(int[] nums) {
    for (int i = 0; i < nums.length - 1; i++)
    {
    int temp = nums[i];
    nums[i] = nums[i + 1];
    nums[i + 1] = temp;
    }
    return nums;
    }

    ReplyDelete
  8. AnarAghaNovember 9, 2020 at 10:36 PM

    public int[] shiftLeft(int[] nums) {
    if(nums.length<=1){
    return nums;
    }
    int[] newNums = new int[nums.length];
    newNums[nums.length-1]=nums[0];
    for(int i=0; i<nums.length-1; i++){
    newNums[i] = nums[i+1];
    }
    return newNums;
    }

    ReplyDelete
  9. ambanielphasMarch 30, 2022 at 5:19 AM

    public int[] shiftLeft(int[] nums) {

    if(nums.length > 0) {
    int temp=nums[0];

    for(int i=0; i < nums.length-1; i++){
    if(nums[i] != nums[nums.length-1]){
    nums[i]=nums[i+1];
    }
    }

    nums[nums.length-1] = temp;
    }

    return nums;
    }

    ReplyDelete
  10. Cema2009June 7, 2022 at 9:02 PM

    With Java Stream and Collections

    public int[] shiftLeft(int[] nums) {
    List numbers = Arrays.stream(nums).boxed().collect(Collectors.toList());
    Collections.rotate(numbers, -1);
    return numbers.stream().mapToInt(i->i).toArray();
    }

    ReplyDelete
  11. nuurJuly 17, 2022 at 9:40 PM

    public int[] shiftLeft(int[] nums) {
    if(nums.length==0)
    return nums;

    int[] t=new int[nums.length];
    t[nums.length-1]=nums[0];

    for(int i=0;i<nums.length-1;i++){
    t[i]=nums[i+1];

    }
    return t;
    }

    ReplyDelete