#include <cstdio>
#include <iostream>
#include <vector>

#define Nmax 100010

using namespace std;

int n , m , i , x , y , OP , ap[30] , sol[Nmax] , final , nr , crt;

vector < int > g[Nmax];

char c , tip[Nmax];

bool sel[Nmax] , ok;

void dfs(int x)
 {
     int i;
     sel[x] = true;

     ap[tip[x]-'a']++;

     if (x == final) ok = true;

     for (i = 0; i < g[x].size() && !ok; ++i)
      if (!sel[g[x][i]])
      {
          dfs(g[x][i]);
          if (!ok) ap[tip[g[x][i]] - 'a']--;
      }


 }


int main()
{
    //freopen("tree.in","r",stdin);
    //freopen("tree.out","w",stdout);

    scanf("%d %d\n", &n , &m);

    for (i = 1; i <= n; ++i)
     scanf("%c", &tip[i]);

    scanf("\n");

    for (i = 1; i < n ; ++i)
    {
        scanf("%d %d", &x , &y);
        g[x].push_back(y);
        g[y].push_back(x);
    }

    nr = n;

    for (i = 1; i <= m; ++i)
    {
        scanf("%d", &OP);

        if (OP == 1)
        {
            crt = 0;
            for (int j = 'a' - 'a'; j <= 'z' - 'a'; ++j)
             ap[j] = 0;

            for (int j = 1; j <= nr; ++j)
             sel[j] = false;

            scanf("%d %d\n", &x , &final);
            ok = false;
            dfs(x);
            for (int j = 'a' - 'a'; j <= 'z' - 'a'; ++j)
             if (ap[j] % 2 == 1) ++crt;

            sol[++sol[0]] = crt;
        }
        else
        {
            scanf("%d %c\n", &x , &c);
            g[x].push_back(++nr);
            g[nr].push_back(x);
            tip[nr] = c;
        }

    }

    for (i = 1; i <= sol[0]; ++i)
     printf("%d\n", sol[i]);



    return 0;
}