LeetCode 2078. Two Furthest Houses With Different Colors

考点	难度
Greedy	Easy

题目

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.

思路

固定最左边的房子，从最右边的房子向左移动直到找到不同，再固定最右边的房子，从最左边的向右移动。比较两个数字的大小，返回大的一个。
leetcode的hint2: Greedily, the maximum distance will come from either the pair of the leftmost house and possibly some house on the right with a different color, or the pair of the rightmost house and possibly some house on the left with a different color.

答案

public int maxDistance(int[] colors) {
        int size = colors.length - 1;
        int half = colors.length / 2;
        for(int i = 0; i <= half; i++) {
            if((colors[size] != colors[i]) || colors[0] != colors[size - i]) {
                return size - i;
            }
        }
        return -1;
}