2078. Two Furthest Houses With Different Colors

Problem

There are n houses evenly lined up on the street, and each house is beautifully painted. You are given a 0-indexed integer array colors of length n, where colors[i] represents the color of the ith house.

Return **the *maximum* distance between two houses with different colors**.

The distance between the ith and jth houses is abs(i - j), where abs(x) is the absolute value of x.

  Example 1:

Input: colors = [1,1,1,6,1,1,1]
Output: 3
Explanation: In the above image, color 1 is blue, and color 6 is red.
The furthest two houses with different colors are house 0 and house 3.
House 0 has color 1, and house 3 has color 6. The distance between them is abs(0 - 3) = 3.
Note that houses 3 and 6 can also produce the optimal answer.

Example 2:

Input: colors = [1,8,3,8,3]
Output: 4
Explanation: In the above image, color 1 is blue, color 8 is yellow, and color 3 is green.
The furthest two houses with different colors are house 0 and house 4.
House 0 has color 1, and house 4 has color 3. The distance between them is abs(0 - 4) = 4.

Example 3:

Input: colors = [0,1]
Output: 1
Explanation: The furthest two houses with different colors are house 0 and house 1.
House 0 has color 0, and house 1 has color 1. The distance between them is abs(0 - 1) = 1.

  Constraints:

• n == colors.length

• 2 <= n <= 100

• 0 <= colors[i] <= 100

• Test data are generated such that at least two houses have different colors.

Solution (Java)

class Solution {
    public int maxDistance(int[] colors) {
        int left = 0;
        int right = colors.length - 1;
        int max = 0;
        while (left < right) {
            if (colors[left] != colors[right]) {
                max = Math.max(max, right - left);
                break;
            } else {
                left++;
            }
        }
        left = 0;
        while (left < right) {
            if (colors[left] != colors[right]) {
                max = Math.max(max, right - left);
                break;
            } else {
                right--;
            }
        }
        return max;
    }
}

Explain:

nope.

Complexity:

• Time complexity : O(n).
• Space complexity : O(n).