| 序号 | 题目:1,2,8,13 | |
|---|---|---|
| 1 | ((13 + 1) + 2) + 8 | |
| 2 | ((13 + 2) + 1) + 8 | |
| 3 | ((13 + 1) + 8) + 2 | |
| 4 | ((13 + 8) + 1) + 2 | |
| 5 | ((13 + 2) + 8) + 1 | |
| 6 | ((13 + 8) + 2) + 1 | |
| 7 | (13 + (8 + 2)) + 1 | |
| 8 | (13 + 2) + (8 + 1) | |
| 9 | (13 + (2 + 1)) + 8 | |
| 10 | (13 + 1) + (8 + 2) | |
| 11 | (13 + (8 + 1)) + 2 | |
| 12 | (13 + 8) + (2 + 1) | |
| 13 | 13 + ((8 + 1) + 2) | |
| 14 | 13 + (8 + (2 + 1)) | |
| 15 | 13 + ((8 + 2) + 1) | |