java实现

给定一个 n 个元素有序的（升序）整型数组 nums 和一个目标值 target ，写一个函数搜索 nums 中的 target，如果目标值存在返回下标，否则返回 -1。

right = nums.length；
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class Solution {
    public int search(int[] nums, int target) {
        int left = 0, right = nums.length;
        while (left < right) {
            int mid = left + ((right-left) >> 1);
            if (nums[mid] == target) {
                return mid;
            } else if (nums[mid] > target) {
                right = mid;
            } else if (nums[mid] < target) {
                left = mid + 1;
            }
        }
        return -1;    
    }
}
right = nums.length - 1；
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class Solution {
    public int search(int[] nums, int target) {
        int left = 0;
        int right = nums.length - 1;
        while (left <= right) {
            int mid = left + (right-left)/2;
            if (nums[mid] > target) {
                right = mid - 1;
            }
            if (nums[mid] < target) {
                left = mid + 1;
            }
            if(nums[mid] == target) {
                return mid;
            }
        }
        return -1;    
    }
}