#ABC232C. [ABC232C] Graph Isomorphism

[ABC232C] Graph Isomorphism

Score : 300300 points

Problem Statement

Takahashi and Aoki each have a toy made by attaching MM cords to NN balls.

In Takahashi's toy, the balls are numbered 1,,N1, \dots, N, and the ii-th cord ties Ball AiA_i and BiB_i.

Similarly, in Aoki's toy, the balls are numbered 1,,N1, \dots, N, and the ii-th cord ties Ball CiC_i and DiD_i.

In each toy, no cord ties a ball to itself, and no two balls are tied by two or more different cords.

Snuke is wondering whether the two toys have the same shape. Here, they are said to have the same shape when there is a sequence PP that satisfies the conditions below.

  • PP is a permutation of (1,,N)(1, \dots, N).
  • For every pair of integers i,ji, j between 11 and NN (inclusive), the following holds.- Balls ii and jj in Takahashi's toy are tied by a cord if and only if Balls PiP_i and PjP_j in Aoki's toy are tied by a cord.

If the two toys have the same shape, print Yes; otherwise, print No.

Constraints

  • 1N81 \leq N \leq 8
  • 0MN(N1)20 \leq M \leq \frac{N(N - 1)}{2}
  • 1Ai<BiN(1iM)1 \leq A_i \lt B_i \leq N \, (1 \leq i \leq M)
  • (Ai,Bi)(Aj,Bj)(ij)(A_i, B_i) \neq (A_j, B_j) \, (i \neq j)
  • 1Ci<DiN(1iM)1 \leq C_i \lt D_i \leq N \, (1 \leq i \leq M)
  • (Ci,Di)(Cj,Dj)(ij)(C_i, D_i) \neq (C_j, D_j) \, (i \neq j)
  • All values in input are integers.

Input

Input is given from Standard Input in the following format:

NN MM

A1A_1 B1B_1

\vdots

AMA_M BMB_M

C1C_1 D1D_1

\vdots

CMC_M DMD_M

Output

If the two toys have the same shape, print Yes; otherwise, print No.

4 4
1 2
1 3
1 4
3 4
1 3
1 4
2 3
3 4
Yes

Takahashi's toy is illustrated on the left in the figure below, and Aoki's is illustrated on the right.

yes1

The following figure shows that the two toys have the same shape. The condition in the statement is satisfied when P=(3,2,1,4)P = (3, 2, 1, 4), for example.

yes2

5 6
1 2
1 3
1 4
3 4
3 5
4 5
1 2
1 3
1 4
1 5
3 5
4 5
No

The two toys do not have the same shape.

no

8 0
Yes