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 * * 如果目标值存在返回下标,否则返回 -1 * @param nums int整型vector * @param target int整型 * @return int整型 */ int t = -1; int search(vector<int>& nums, int target) { // write code here if (nums.empty()) { return -1; } t = target; return s(nums, 0, nums.size() - 1); } int s(vector<int> &nums, int b, int e) { int m = (b + e) / 2; if (nums[m] == t) { do { if (nums[m - 1] != t) { break; } } while(--m); return m; } if (e == b) { return -1; } if (nums[m] > t) { return s(nums, b, m - 1); } return s(nums, m + 1, e); } };