array
文章目录
稀疏数组
压缩棋盘。记录数组一共有几行几列，有多少个不同的值
| 11 | 22 | 0 | 0 | 0 | 0 | 0 |
| 0 | 33 | 44 | 0 | 0 | 0 | 0 |
| 0 | 0 | 55 | 66 | 77 | 0 | 0 |
| 0 | 0 | 0 | 0 | 0 | 88 | 0 |
| 0 | 0 | 0 | 0 | 0 | 0 | 99 |
| 行 | 列 | 值 | |
|---|---|---|---|
| [0] | 5 | 7 | 9 |
| [1] | 0 | 0 | 11 |
| [2] | 0 | 1 | 22 |
| [3] | 1 | 1 | 33 |
| [4] | 1 | 2 | 44 |
| [5] | 2 | 2 | 55 |
| [6] | 2 | 3 | 66 |
| [7] | 2 | 4 | 77 |
| [8] | 3 | 5 | 88 |
| [9] | 4 | 6 | 99 |
环形队列
限制rear赶上front，即队尾结点与队首结点之间至少留有一个元素的空间
考虑rear<front的情况
- 队列空：front==rear
- 队列满：(rear+1)%size==front
- 队列长度：(rear-front+size)%size