| Subtask no. | Testdata Range | Constraints | Score | 
|---|---|---|---|
| 1 | 0~1 | 範例測資 | 0 / 0 | 
| 2 | 2~15 | $\forall 1 \leq i \leq M,\ s_i=t_i=i$ | 0.49 / 0.48763 | 
| 3 | 16~53 | $M=N-1$,$\forall 1 \leq i < M,\ u_i=i,\ v_i=i+1$ | 0.51 / 0.51237 | 
| 4 | 54~61 | $N \leq 50, M \leq 100$ | 4 / 4 | 
| 5 | 54~72 | $N \leq 200, M \leq 1000$ | 1 / 1 | 
| 6 | 9~15, 35~96 | $N \leq 400, M \leq 1000$ | 0 / 4 | 
| 7 | 0~120 | 無額外限制 | 0 / 90 |