1
class Solution {
2
 public:
3
  int maxDistance(vector<int> &colors) {
4
    int Max = INT_MIN;
5
    int N = colors.size();
6

7
    // find the first house from the end which does not match the color of house
8
    // at front
9
    int j = N;
10
    while (--j >= 0 && colors[0] == colors[j]) {
11
    } // worst-case O(n)
12
    Max = abs(j - 0);
13

14
    // find the first house from the front which does not match the color of
15
    // house at back
16
    j = -1;
17
    while (++j < N && colors[N - 1] == colors[j]) {
18
    } // worst-case O(n)
19
    Max = max(Max, abs(j - (N - 1)));
20

21
    return Max;
22
  }
23
};