日拱一卒

1 一周见闻

1.1 技术文章

1.2 泛互联网文章

2 技术总结

3 Algorithm(算法题)

• 187. 重复的DNA序列

class Solution {
    public List<String> findRepeatedDnaSequences(String s) {
        int n  = s.length();
        Map<String, Integer> count = new HashMap<>();
        List<String> ret = new ArrayList<>();
        for(int i= 0; i + 10 <= n; i++) {
            String cur = s.substring(i, i + 10);
            Integer curCount = count.getOrDefault(cur, 0);
            if(curCount == 1) {
                ret.add(cur);
            } 
            count.put(cur, curCount + 1);
        }
        return ret;
    }
}

• 1838. 最高频元素的频数

class Solution {
    public int maxFrequency(int[] nums, int k) {
        Arrays.sort(nums);
        int n = nums.length;
        long total = 0;
        int l = 0, res = 1;
        for (int r = 1; r < n; ++r) {
            total += (long) (nums[r] - nums[r - 1]) * (r - l);
            while (total > k) {
                total -= nums[r] - nums[l];
                ++l;
            }
            res = Math.max(res, r - l + 1);
        }
        return res;
    }
}