Day01.算法训练

704. 二分查找

class Solution {
    public int search(int[] nums, int target) {
        int left = 0;
        int right = nums.length - 1;
        return find(nums, left, right, target);
    }

    public int find(int[] nums, int left, int right, int target) {
        while (left < right) {
            int middle = (left + right) / 2;
            if (target > nums[middle]) {
                left = middle + 1;
            } else if (target < nums[middle]) {
                right = middle - 1;
            } else {
                return middle;
            }
        }
        if (left == right) {
            if (target == nums[right]) {
                return right;
            }
        }
        return -1;
    }
}

27. 移除元素

class Solution {
    public int removeElement(int[] nums, int val) {
        int fast = 0;
        int slow = 0;
        for (int i = 0; i < nums.length; i++) {
            if (nums[fast] != val) {
                nums[slow++] = nums[fast++];
            } else {
                fast++;
            }
        }
        return slow;
    }
}