【每日一题Day340】LC2251花期内花的数目 | 差分+哈希表+排序 排序+二分查找

class Solution {
    public int[] fullBloomFlowers(int[][] flowers, int[] people) {
        int max = Integer.MIN_VALUE;
        for (int[] flower : flowers){
            max = Math.max(flower[1], max);
        }
        for (int index : people){
            max = Math.max(index, max);
        }
        int m = people.length;
        int[] d = new int[max + 2];
        int[] res = new int[m];
        for (int[] flower : flowers){
            int start = flower[0], end = flower[1];
            d[start]++;
            d[end + 1]--;
        }
        for (int i = 1; i <= max; i++){
            d[i] += d[i - 1];
        }
        for (int i = 0; i < m; i++){
            res[i] = d[people[i]];
        }
        return res;
    }
}