1. 区间问题
AcWing 905. 区间选点 https://www.acwing.com/solution/content/80992/
AcWing 908. 最大不相交区间数量 https://www.acwing.com/solution/content/81010/
AcWing 906. 区间分组 https://www.acwing.com/solution/content/81023/
AcWing 907. 区间覆盖 https://www.acwing.com/solution/content/81102/
2. 哈夫曼树
AcWing 148. 合并果子 https://www.acwing.com/solution/content/81088/
3. 排序不等式
AcWing 913. 排队打水 https://www.acwing.com/solution/content/81475/
4. 绝对值不等式
AcWing 104. 货仓选址 https://www.acwing.com/solution/content/81479/
5. 推公式
AcWing 125. 耍杂技的牛 https://www.acwing.com/solution/content/81486/
