题解 | #二分查找-I#

class Solution {
  public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     *
     * @param nums int整型vector
     * @param target int整型
     * @return int整型
     */
    int search(vector<int>& nums, int target) {
        int left = 0;
        int right = nums.size() - 1;
        int mid;

        if (nums.empty()) {
            return -1;
        } else if (target < nums.front() || target > nums.back()) {
            return -1;
        }

        while (left <= right) {
            mid = left + (right - left) / 2;
            if (nums.at(mid) == target) {
                return mid;
            } else if (nums.at(mid) < target) {
                left = mid + 1;
            } else {
                right = mid - 1;
            }
        }

        return -1;
    }
};