#include <queue>
#include <vector>
#include <iostream>
using namespace std;
int main() {
	int N, M; string S;
	cin >> N >> M >> S;
	vector<vector<int> > G(N);
	vector<int> ca(N), cb(N);
	for (int i = 0; i < M; ++i) {
		int a, b;
		cin >> a >> b; --a, --b;
		G[a].push_back(b);
		G[b].push_back(a);
		if (S[a] == 'A') ++ca[b]; else ++cb[b];
		if (S[b] == 'A') ++ca[a]; else ++cb[a];
	}
	queue<int> que;
	for (int i = 0; i < N; ++i) {
		if (ca[i] == 0 || cb[i] == 0) {
			que.push(i);
		}
	}
	int cnt = 0;
	while (!que.empty()) {
		int u = que.front(); que.pop();
		++cnt;
		for (int i : G[u]) {
			bool notyet = (ca[i] != 0 && cb[i] != 0);
			if (S[u] == 'A') --ca[i]; else --cb[i];
			if (notyet && (ca[i] == 0 || cb[i] == 0)) {
				que.push(i);
			}
		}
	}
	cout << (cnt != N ? "Yes" : "No") << endl;
	return 0;
}
### Prompt

Your challenge is to write 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 <vector>
#include <iostream>
using namespace std;
int main() {
	int N, M; string S;
	cin >> N >> M >> S;
	vector<vector<int> > G(N);
	vector<int> ca(N), cb(N);
	for (int i = 0; i < M; ++i) {
		int a, b;
		cin >> a >> b; --a, --b;
		G[a].push_back(b);
		G[b].push_back(a);
		if (S[a] == 'A') ++ca[b]; else ++cb[b];
		if (S[b] == 'A') ++ca[a]; else ++cb[a];
	}
	queue<int> que;
	for (int i = 0; i < N; ++i) {
		if (ca[i] == 0 || cb[i] == 0) {
			que.push(i);
		}
	}
	int cnt = 0;
	while (!que.empty()) {
		int u = que.front(); que.pop();
		++cnt;
		for (int i : G[u]) {
			bool notyet = (ca[i] != 0 && cb[i] != 0);
			if (S[u] == 'A') --ca[i]; else --cb[i];
			if (notyet && (ca[i] == 0 || cb[i] == 0)) {
				que.push(i);
			}
		}
	}
	cout << (cnt != N ? "Yes" : "No") << endl;
	return 0;
}
```