摘要: 题目链接:https://www.acwing.com/activity/content/problem/content/830/ 突然发现把二维前缀和这小尾巴漏了 显而易见:s[i][j] = s[i-1][j] + s[i][j-1] - s[i-1][j-1] + a[i] [j]。 由此可以 阅读全文
posted @ 2022-07-24 23:09 爱吃虾滑 阅读(37) 评论(0) 推荐(0)