#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
using namespace std;

const int maxn = 2e5;
int n, m;
char col[maxn + 1];

vector<int> g[maxn * 4];

void Add(int u, int v) {
  char a = col[u], b = col[v];
  int t;
  if (a == 'A') {
    if (b == 'A') {
      t = 0;
    } else {
      t = 1;
    }
  } else {
    if (b == 'A') {
      t = 3;
    } else {
      t = 2;
    }
  }
  g[t * n + u].push_back((t + 1 & 3) * n + v);
}

int vis[maxn * 4];

void Dfs(int u) {
  if (vis[u] == 1) {
    puts("Yes");
    exit(0);
  }
  vis[u] = 1;
  for (int v : g[u]) {
    if (vis[v] != 2) {
      Dfs(v);
    }
  }
  vis[u] = 2;
}

bool Main(void) {
  for (int i = 0; i < 4 * n; ++i) {
    if (vis[i] == 0) Dfs(i);
  }
  return false;
}

int main(void) {
  scanf("%d%d", &n, &m);
  scanf("%s", col);
  for (int i = 0; i < m; ++i) {
    int u, v;
    scanf("%d%d", &u, &v);
    --u; --v;
    Add(u, v);
    Add(v, u);
  }
  puts(Main() ? "Yes" : "No");
  return 0;
}

### Prompt

Please create a solution in cpp 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 <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
using namespace std;

const int maxn = 2e5;
int n, m;
char col[maxn + 1];

vector<int> g[maxn * 4];

void Add(int u, int v) {
  char a = col[u], b = col[v];
  int t;
  if (a == 'A') {
    if (b == 'A') {
      t = 0;
    } else {
      t = 1;
    }
  } else {
    if (b == 'A') {
      t = 3;
    } else {
      t = 2;
    }
  }
  g[t * n + u].push_back((t + 1 & 3) * n + v);
}

int vis[maxn * 4];

void Dfs(int u) {
  if (vis[u] == 1) {
    puts("Yes");
    exit(0);
  }
  vis[u] = 1;
  for (int v : g[u]) {
    if (vis[v] != 2) {
      Dfs(v);
    }
  }
  vis[u] = 2;
}

bool Main(void) {
  for (int i = 0; i < 4 * n; ++i) {
    if (vis[i] == 0) Dfs(i);
  }
  return false;
}

int main(void) {
  scanf("%d%d", &n, &m);
  scanf("%s", col);
  for (int i = 0; i < m; ++i) {
    int u, v;
    scanf("%d%d", &u, &v);
    --u; --v;
    Add(u, v);
    Add(v, u);
  }
  puts(Main() ? "Yes" : "No");
  return 0;
}

```