Java > Array-2 > twoTwo (CodingBat Solution)

Problem:

Given an array of ints, return true if every 2 that appears in the array is next to another 2.

twoTwo({4, 2, 2, 3}) → true
twoTwo({2, 2, 4}) → true
twoTwo({2, 2, 4, 2}) → false


Solution:

public boolean twoTwo(int[] nums) {
int index =0;
for (int i=0; i<(nums.length); i++)
{
if(nums[i]==2)
{
i++;
if(!(i<(nums.length)) || nums[i] !=2) return false;
while(i<nums.length && nums[i] ==2) i++;
}
}
return true;
}

9 comments:

  1. UnknownApril 9, 2017 at 7:29 AM

    static boolean twoTwo(int[] nums) {
    int len = nums.length;
    boolean result = true;
    boolean found = false;

    for(int i=0; i<len; i++){
    if(nums[i] !=2) found = false;

    if(nums[i] ==2 && found) result = true;

    if(nums[i] ==2 && !found){
    found = true;
    result = false;
    }

    }
    return result;
    }

    ReplyDelete
  2. UnknownSeptember 12, 2017 at 6:43 AM

    public boolean twoTwo(int[] nums) {

    for (int i=0; i= 1 && nums[i-1] == 2)
    continue;
    if (i < (nums.length-1) && nums[i+1] == 2)
    continue;
    return false;
    }
    return true;

    ReplyDelete
  3. AnonymousMarch 13, 2019 at 2:17 AM

    public boolean twoTwo(int[] nums) {
    if(nums.length == 0) {
    return true;
    }

    if(nums.length == 1 && nums[0] == 2)
    return false;

    if(nums[nums.length -1] == 2 && nums[nums.length - 2] != 2)
    return false;

    for(int i = 1; i < nums.length - 1; i++) {
    if(nums[i] == 2) {
    if(nums[i-1] != 2 && nums[i+1] != 2) {
    return false;
    }
    }
    }
    return true;
    }

    ReplyDelete
  4. UnknownJuly 28, 2020 at 12:06 PM

    public boolean twoTwo(int[] nums) {
    if (nums.length == 1 && nums[0] == 2)
    {
    return false;
    }
    for (int i = 0; i < nums.length - 1; i++)
    {
    if ((nums[i] == 2 && nums[i + 1] != 2) || (i == nums.length - 2 && nums[i] != 2 && nums[i + 1] == 2))
    {
    return false;
    }
    else if (nums[i] == 2 && nums[i + 1] == 2)
    {
    i++;
    }
    }
    return true;
    }

    ReplyDelete
  5. UnknownSeptember 12, 2020 at 9:38 AM

    public boolean twoTwo(int[] nums) {
    int flag=0;
    int flag1=0;

    for(int i=0;inums.length-1 )
    {
    break;
    }
    else
    {
    if(nums[i+1]==2)
    {
    flag=1;
    }


    }


    }
    else
    {
    if(i+1> nums.length-1)
    {
    break;

    }
    else
    {
    if(nums[i+1]==2)
    {
    flag=0;
    }
    }
    }

    }
    if(flag==1)
    return true;
    else if(flag1==0)
    return true;
    else
    return false;
    }

    ReplyDelete
  6. UnknownFebruary 10, 2021 at 11:09 PM

    public boolean twoTwo(int[] nums)
    {
    if(nums.length == 1 && nums[0] == 2)
    return false;

    for(int i = 0; i<nums.length ; i++)
    {
    if(nums[i] == 2)
    {
    if(i+1 < nums.length && nums[i+1] != 2)
    {
    return false;
    }
    if(i == nums.length-1 && nums[i-1] != 2 ) // only for last element
    {
    return false;
    }
    else
    {
    i += 1;
    }
    }
    }

    return true;
    }

    ReplyDelete
  7. IstvánNovember 20, 2021 at 1:32 PM

    public boolean twoTwo(int[] nums) {
    int len = nums.length;

    for (int i = 0; i < len; i++) {
    if (nums[i] == 2) {
    i++;
    if (i == len || nums[i] != 2) {
    return false;
    } else {
    i++;
    }
    }
    }
    return true;

    }

    ReplyDelete
  8. nuurJuly 16, 2022 at 10:06 AM

    MORE EASY TO UNDERISTAND



    public boolean twoTwo(int[] nums) {
    int count=0;

    for(int i=0;i1||count==0;
    }

    ReplyDelete