#include<queue>
#include<cstdio>
#include<cctype>
#include<vector>
const int N=200007;
int read(){int x=0,c=getchar();while(!isdigit(c))c=getchar();while(isdigit(c))x=x*10+c-48,c=getchar();return x;}
std::vector<int>e[N];std::queue<int>q;
int n,m,ans,vis[N],deg[N][2];char col[N];
int main()
{
    n=read(),m=read(),scanf("%s",col+1);
    for(int i=1,u,v;i<=m;++i) u=read(),v=read(),e[u].push_back(v),e[v].push_back(u),++deg[u][col[v]=='B'],++deg[v][col[u]=='B'];
    for(int i=1;i<=n;++i) if(!deg[i][0]||!deg[i][1]) ++ans,q.push(i),vis[i]=1;
    for(int u;!q.empty();)
    {
    u=q.front(),q.pop();
    for(int v:e[u]) if(!vis[v]&&!--deg[v][col[u]=='B']) ++ans,q.push(v),vis[v]=1;
    }
    puts(ans==n? "No":"Yes");
}
### Prompt

Your task is to create a Cpp solution to the following problem:

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` or `B`.
* 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

### Response

```cpp
#include<queue>
#include<cstdio>
#include<cctype>
#include<vector>
const int N=200007;
int read(){int x=0,c=getchar();while(!isdigit(c))c=getchar();while(isdigit(c))x=x*10+c-48,c=getchar();return x;}
std::vector<int>e[N];std::queue<int>q;
int n,m,ans,vis[N],deg[N][2];char col[N];
int main()
{
    n=read(),m=read(),scanf("%s",col+1);
    for(int i=1,u,v;i<=m;++i) u=read(),v=read(),e[u].push_back(v),e[v].push_back(u),++deg[u][col[v]=='B'],++deg[v][col[u]=='B'];
    for(int i=1;i<=n;++i) if(!deg[i][0]||!deg[i][1]) ++ans,q.push(i),vis[i]=1;
    for(int u;!q.empty();)
    {
    u=q.front(),q.pop();
    for(int v:e[u]) if(!vis[v]&&!--deg[v][col[u]=='B']) ++ans,q.push(v),vis[v]=1;
    }
    puts(ans==n? "No":"Yes");
}
```