Java > Array-2 > modThree (CodingBat Solution)

Problem:

Given an array of ints, return true if the array contains either 3 even or 3 odd values all next to each other.

modThree({2, 1, 3, 5}) → true
modThree({2, 1, 2, 5}) → false
modThree({2, 4, 2, 5}) → true


Solution:

public boolean modThree(int[] nums) {
  int odd = 0;
  int even = 0;
  
  for (int i = 0; i < nums.length; i++) {
    if (nums[i] % 2 == 0) {
      even++;
      if (odd < 3) odd = 0;
    }
    else {
      odd++;
      if (even < 3) even = 0;
    }
  }
  return (odd == 3 || even == 3);
}

6 comments:

  1. AnonymousJuly 9, 2016 at 3:11 AM

    Here's a more general/quicker way:

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

    ReplyDelete
  2. UnknownApril 4, 2018 at 1:38 PM

    public boolean modThree(int[] nums) {

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

    ReplyDelete
  3. UnknownApril 21, 2018 at 3:26 AM

    function modThree() {
    var intArray = [0,2, 4, 3, 5];
    var modThreeFlag = false;
    for (var i = 0; i < intArray.length - 2; i++) {
    if (intArray[i] % 2 == 0 && intArray[i + 1] % 2 == 0 && intArray[i + 2] % 2 == 0) {
    modThreeFlag = true;
    break;
    }
    else if (intArray[i] % 2 == 1 && intArray[i + 1] % 2 == 1 && intArray[i + 2] % 2 == 1) {
    modThreeFlag = true;
    break;
    }
    else {
    modThreeFlag = false;
    }
    }
    var intArrayString = intArray.join().toString();
    document.getElementById("outputText").value = modThreeFlag;
    }

    ReplyDelete
  4. UnknownDecember 26, 2021 at 10:15 PM

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

    ReplyDelete
  5. AnonymousSeptember 18, 2023 at 11:05 PM

    public boolean modThree(int[] nums) {
    int even=0;
    int odd =0;
    boolean flag = false;

    for(int i=0 ; i<nums.length ;i++){
    if(nums[i]%2==0) {
    even++;
    if(even==3)
    {
    flag = true ;
    break;

    }
    }
    else {
    even=0;
    }

    if(nums[i]%2!=0) {
    odd++;
    if(odd==3)
    {
    flag = true ;
    break;

    }
    }
    else {
    odd=0;
    }
    }

    return flag;

    }

    ReplyDelete