#D8980. ABland Yard
ABland Yard
ABland Yard
You are given an undirected graph consisting of N vertices and M edges. The vertices are numbered 1 to N, and the edges are numbered 1 to M. In addition, each vertex has a label, A
or B
. The label of Vertex i is s_i. Edge i bidirectionally connects vertex a_i and b_i.
The phantom thief Nusook likes to choose some vertex as the startpoint and traverse an edge zero or more times. Today, he will make a string after traveling as above, by placing the labels of the visited vertices in the order visited, beginning from the startpoint.
For example, in a graph where Vertex 1 has the label A
and Vertex 2 has the label B
, if Nusook travels along the path 1 \rightarrow 2 \rightarrow 1 \rightarrow 2 \rightarrow 2, the resulting string is ABABB
.
Determine if Nusook can make all strings consisting of A
and B
.
Constraints
- 2 \leq N \leq 2 \times 10^{5}
- 1 \leq M \leq 2 \times 10^{5}
- |s| = N
- s_i is
A
orB
. - 1 \leq a_i, b_i \leq N
- The given graph may NOT be simple or connected.
Input
Input is given from Standard Input in the following format:
N M s a_1 b_1 : a_{M} b_{M}
Output
If Nusook can make all strings consisting of A
and B
, print Yes
; otherwise, print No
.
Examples
Input
2 3 AB 1 1 1 2 2 2
Output
Yes
Input
4 3 ABAB 1 2 2 3 3 1
Output
No
Input
13 23 ABAAAABBBBAAB 7 1 10 6 1 11 2 10 2 8 2 11 11 12 8 3 7 12 11 2 13 13 11 9 4 1 9 7 9 6 8 13 8 6 4 10 8 7 4 3 2 1 8 12 6 9
Output
Yes
Input
13 17 BBABBBAABABBA 7 1 7 9 11 12 3 9 11 9 2 1 11 5 12 11 10 8 1 11 1 8 7 7 9 10 8 8 8 12 6 2 13 11
Output
No
inputFormat
Input
Input is given from Standard Input in the following format:
N M s a_1 b_1 : a_{M} b_{M}
outputFormat
Output
If Nusook can make all strings consisting of A
and B
, print Yes
; otherwise, print No
.
Examples
Input
2 3 AB 1 1 1 2 2 2
Output
Yes
Input
4 3 ABAB 1 2 2 3 3 1
Output
No
Input
13 23 ABAAAABBBBAAB 7 1 10 6 1 11 2 10 2 8 2 11 11 12 8 3 7 12 11 2 13 13 11 9 4 1 9 7 9 6 8 13 8 6 4 10 8 7 4 3 2 1 8 12 6 9
Output
Yes
Input
13 17 BBABBBAABABBA 7 1 7 9 11 12 3 9 11 9 2 1 11 5 12 11 10 8 1 11 1 8 7 7 9 10 8 8 8 12 6 2 13 11
Output
No
样例
13 17
BBABBBAABABBA
7 1
7 9
11 12
3 9
11 9
2 1
11 5
12 11
10 8
1 11
1 8
7 7
9 10
8 8
8 12
6 2
13 11
No