二分查找

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public int binarySearch(int[] nums, int target) {
        // 二分查找
        int left = 0, right = nums.length - 1;
        int mid = 0;
        while (left <= right) {
            mid = left + ((right - left) >> 1);
            if (nums[mid] == target) {
                return mid;
            }
            // 二分查找的模板
            if (nums[mid] < target) {
                left = mid + 1;
            } else if (nums[mid] > target) {
                right = mid - 1;
            }
        }

        return left;
    }