#include <cstdio>
#include <vector>

using namespace std;

struct Node {
    char l;
    Node *parent;
};

int n,m, x, y, c, p, ans;
char l;
vector<Node*> tree;
long long f[30];



void odd(int s, int s2, bool last=true) {
    Node *p = tree[s];
    if (p == NULL)
        return;
    while (p->parent != NULL) {
        if (p == tree[s2]) {
            last = false;
            break;
        }
        f[p->l - 'a']++;
        p = p->parent;
    }
    if (last)
        f[p->l - 'a']++;
}

int main () {


    scanf("%d %d\n", &n, &m);
    tree.push_back(new Node);
    for (int i=0; i<n; ++i) {
        tree.push_back(new Node);
        scanf("%c", &tree[i+1]->l);
        tree[i+1]->parent = NULL;
    }

    scanf("%c", &l);
    for (int i=0; i<n-1;++i) {
        scanf("%d %d", &x, &y);
        tree[y]->parent = tree[x];
    }
    ++n;
    for (;m;--m) {
        scanf("%d ", &c);
        if (c == 2) {
            scanf("%d %c", &p, &l);
            tree.push_back(new Node);
            tree[n]->l = l;
            tree[n]->parent = tree[p];
            ++n;
        }
        else if (c == 1) {
            for (int i=0; i<30; ++i)
                f[i] = 0;
            scanf("%d %d", &x, &y);
            odd(x, y);
            odd(y, x, false);
            ans = 0;
            for (int i=0; i<26; ++i)
                if (f[i] %2 == 1)
                    ans++;
            printf("%d\n", ans);
        }
    }


    return 0;
}