704.二分查找 27.移除元素

704.二分查找

Accept

注意 循环条件 left <= right

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

27.移除元素

Accept

1.快慢指针，经典可for while组合。2.这道 while 可换成if

public class test {
    public static void main(String[] args) {
       int a[] = {0,1,2,2,3,0,4,2};
       Arrays.sort(a);
       int slow = 0, fast = 0;
       for (; fast < a.length; fast++) {
            while (a[slow] != a[fast]){
                a[++slow] = a[fast];
            }
        }
       for (int k = 0; k <= slow; k++) System.out.println(a[k]);
    }
}