| type | rice | flour | bean | steak | chicken |
| NW | 2 | 5 | 2 | 5 | 2 |
| OB | 4 | 5 | 3 | 5 | 2 |
| NW | 5 | 5 | 5 | 5 | 5 |
| NW | 3 | 5 | 2 | 2 | 2 |
| OB | 4 | 5 | 2 | 3 | 3 |
| NW | 4 | 5 | 3 | 5 | 4 |
| NW | 2 | 2 | 2 | 2 | 2 |
| OB | 2 | 5 | 2 | 1 | 1 |
| OB | 5 | 5 | 3 | 4 | 3 |
| OW | 4 | 5 | 2 | 3 | 2 |
| OB | 3 | 5 | 2 | 4 | 3 |
| OW | 3 | 5 | 4 | 3 | 3 |
| OW | 5 | 5 | 2 | 2 | 5 |
各位大侠,我需要分类统计NW、OB和OW中每类食物分别选“1、2、3、4、5”的人数各有多少?用R应该怎么编程呢?跪求!谢谢!