{ "id": 3463, "name": "alternating_groups_i", "difficulty": "Easy", "link": "https://leetcode.com/problems/alternating-groups-i/", "date": "2024-06-22 00:00:00", "task_description": "There is a circle of red and blue tiles. You are given an array of integers `colors`. 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**. Every 3 contiguous tiles in the circle with **alternating** colors (the middle tile has a different color from its **left** and **right** tiles) is called an **alternating** group. Return the number of **alternating** groups. **Note** that since `colors` represents a **circle**, the **first** and the **last** tiles are considered to be next to each other. **Example 1:** **Input:** colors = [1,1,1] **Output:** 0 **Explanation:** **Example 2:** **Input:** colors = [0,1,0,0,1] **Output:** 3 **Explanation:** Alternating groups: ******** **Constraints:** `3 <= colors.length <= 100` `0 <= colors[i] <= 1`", "public_test_cases": [ { "label": "Example 1", "input": "colors = [1,1,1]", "output": "0 " }, { "label": "Example 2", "input": "colors = [0,1,0,0,1]", "output": "3 " } ], "private_test_cases": [ { "input": [ 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0 ], "output": 11 }, { "input": [ 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1 ], "output": 30 }, { "input": [ 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1 ], "output": 5 }, { "input": [ 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0 ], "output": 19 }, { "input": [ 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0 ], "output": 11 } ], "haskell_template": "numberOfAlternatingGroups :: [Int] -> Int\nnumberOfAlternatingGroups colors ", "ocaml_template": "let numberOfAlternatingGroups (colors: int list) : int = ", "scala_template": "def numberOfAlternatingGroups(colors: List[Int]): Int = { \n \n}", "java_template": "class Solution {\n public int numberOfAlternatingGroups(int[] colors) {\n \n }\n}", "python_template": "class Solution(object):\n def numberOfAlternatingGroups(self, colors):\n \"\"\"\n :type colors: List[int]\n :rtype: int\n \"\"\"\n " }