[LeetCode][H] 4. 寻找两个有序数组的中位数

class Solution {
    public double findMedianSortedArrays(int[] A, int[] B) {
        int m = A.length;
        int n = B.length;
        if (m > n) {
            int[] temp = A;
            A = B;
            B = temp;

            int t = m;
            m = n;
            n = t;
        }

        int left = 0;
        int right = m;
        int halfCount = (m + n + 1) / 2;
        while (left <= right) {
            int i = left + (right - left) / 2;
            int j = halfCount - i;
            if (i < right && A[i] < B[j - 1]) {
                left = i + 1;
            } else if (i > left && B[j] < A[i - 1]) {
                right = i - 1;
            } else {
                int maxLeft;
                if (i == 0) {
                    maxLeft = B[j - 1];
                } else if (j == 0) {
                    maxLeft = A[i - 1];
                } else {
                    maxLeft = Math.max(A[i - 1], B[j - 1]);
                }

                if ((m + n) % 2 == 1) {
                    return maxLeft;
                }

                int minRight;
                if (i == m) {
                    minRight = B[j];
                } else if (j == n) {
                    minRight = A[i];
                } else {
                    minRight = Math.min(A[i], B[j]);
                }

                return (maxLeft + minRight) / 2.0;
            }
        }
        return 0.0;
    }
}