Tricky interview puzzle: get longest sequence by flipping 1 bit

Question

A friend of mine got this question during an interview. The interview ended with no luck for him, but still, we're very curious to hear the solution. The question is as follows:

Modify the code below (change 3 lines maximum) so the function will return the length of the longest sequence of the same bit, if you would flip one bit in the given array. Note: the method's parameter is a bits array.

For example: take the bits array: "11001001010". By flipping the 5th bit from "1" to "0", we'll get: "11000001010" and the result would be: 5.

private static int solution(int[] a) {

    int n = a.length;
    int result = 0;
    int i;

    for (i = 0; i < n - 1; i++) {

        if(a[i] == a[i + 1])
            result = result  + 1;
    }
    int r = 0;
    for (i = 0; i < n; i++) {

        int count = 0;
        if(i > 0)   {
            if(a[i - 1] != a[i])
                count = count + 1;
            else
                count = count - 1;
        }
        if(i < n - 1)   {
            if(a[i + 1] != a[i])
                count = count + 1;
            else
                count = count - 1;
        }

        if(count > r)
            r = count;
    }

    return result + r;
}