There is a circle of red and blue tiles. You are given an array of integers colors and an integer k. The color of tile i is represented by colors[i]: colors[i] == 0 means that tile i is red. colors[i] == 1 means that tile i is blue. An alternating g

numberOfAlternatingGroups.js

/**
 * @param {number[]} colors
 * @param {number} k
 * @return {number}
 */
var numberOfAlternatingGroups = function(colors, k) {
    // Extend the colors array to handle the circular nature by appending the first (k - 1) elements to the end
    colors.push(...colors.slice(0, k - 1)); 
    
    let count = 0; // Counter for the number of alternating groups
    let left = 0; // Left pointer for the sliding window
    
    // Iterate through the extended colors array with the right pointer
    for (let right = 0; right < colors.length; right++) {
        // If the current tile is the same color as the previous tile, reset the left pointer
        if (right > 0 && colors[right] === colors[right - 1]) {
            left = right;  
        }
        
        // If the current window size (right - left + 1) is at least k, count it as an alternating group
        if (right - left + 1 >= k) {
            count++;  
        }
    }
    
    return count; // Return the total number of alternating groups
};