算法刷题打卡01

开始每天必须刷两道算法题, 具体题目可参考https://www.acwing.com/activity/content/record/40/1/

AC817: 数组去重

#include <iostream>
#include <algorithm>

using namespace std;

const int N = 1005;
int q[N];
int main() {
    int n;
    cin >> n;
    for(int i = 0; i < n; i ++) {
        cin >> q[i];
    }
    sort(q, q+n);
    int k = 1;
    for(int i = 1; i < n; i ++) {
        if(q[i] != q[k-1]) {
            q[k++] = q[i];
        }
    }
    cout << k << endl;
    
    return 0;
}

LC80: 删除有序数组重复元素

class Solution {
    public int removeDuplicates(int[] nums) {
        if(nums.length <= 2) return nums.length;
        int len = nums.length;
        int k = 1;
        int count = 1;
        for(int i = 1; i < len; i ++) {
            if(nums[i] != nums[k-1]) {
                nums[k ++] = nums[i];
                count = 1;
            } else {
                if(count >= 2) continue;
                else {
                    count ++;
                    nums[k ++] = nums[i];
                }
                
            }
        }
        return k;
    }
}

总结: 两道题目主要是使用双指针, 核心代码是a[i] = a[k-1], 体验双指针技巧的迭代过程和魅力~~~