给定一个按照升序排列的整数数组 nums，和一个目标值 target。找出给定目标值在数组中的开始位置和结束位置。
你的算法时间复杂度必须是 O(log n) 级别。
如果数组中不存在目标值，返回 [-1, -1]。
示例 1:
输入: nums = [5,7,7,8,8,10], target = 8
输出: [3,4]
示例 2:
输入: nums = [5,7,7,8,8,10], target = 6
输出: [-1,-1]
解：
public int[] searchRange(int[] nums, int target) {
int[] rtn = new int[2];
rtn[0] = -1;
rtn[1] = -1;
if (nums.length == 0) {
return rtn;
}
if (nums.length == 1) {
if (nums[0] == target) {
rtn[0] = 0;
rtn[1] = 0;
return rtn;
} else {
return rtn;
}
}
int left = 0;
int right = nums.length - 1;
while (left <= right) {
int mid = (left + right) / 2;
if (nums[mid] > target) {
right = --mid;
} else if (nums[mid] < target) {
left = ++mid;
} else {
int innerLeft = mid;
int innerRight = mid;
while (innerLeft >= 0 && nums[innerLeft] == target) {
innerLeft--;
}
while (innerRight <= nums.length - 1 && nums[innerRight] == target) {
innerRight++;
}
rtn[0] = innerLeft + 1;
rtn[1] = innerRight - 1;
return rtn;
}
}
return rtn;
}
