#include<stdio.h>
#include<stdlib.h>
#include<math.h>

typedef struct {
    int tata;
    int info;
    int mask;
    int level;
} NODE;

typedef struct lista {
    int v;
    struct lista *next;
} LISTA;

typedef struct query {
    int x, y;
    struct query *next;
} QUERY;

NODE nodes[100001];
LISTA *lista[100001];
QUERY *queries, *last;
int n, m, t, x, y, p[100001], h = 0, root, vLca, tans, ans;
char sir[100001];

LISTA* newNeightboar(int x, LISTA *next) {
    LISTA *node = (LISTA*)malloc(sizeof(LISTA));
    node->v = x;
    node->next = next;
    return node;
}

void newQuery(int x, int y) {
    QUERY *q = (QUERY*)malloc(sizeof(QUERY));
    q->x = x;
    q->y = y;
    q->next = 0;
    if(queries == NULL) {
        queries = last = q;
    }
    else {
        last->next = q;
        last = q;
    }
}

void computeP(int node, int l) {
    if(nodes[node].level < l)
        p[node] = root;
    else {
        if(!(nodes[node].level % l))
            p[node] = nodes[node].tata;
        else
            p[node] = p[nodes[node].tata];
    }
    LISTA *q = lista[node];
    while(q) {
        computeP(q->v, l);
        q = q->next;
    }
}

int lca(int x, int y) {
    while(p[x] != p[y]) {
        if(nodes[x].level > nodes[y].level)
            x = p[x];
        else
            y = p[y];
    }
    while(x != y)
        if(nodes[x].level > nodes[y].level)
            x = nodes[x].tata;
        else
            y = nodes[y].tata;
    return x;
}

void masks(int node, int mask) {
    nodes[node].mask = mask ^ nodes[node].info;
    LISTA *q = lista[node];
    while(q) {
        masks(q->v, nodes[node].mask);
        q = q->next;
    }
}

int main() {
    FILE *f = fopen("in.in", "r");
    scanf("%d%d", &n, &m);
    scanf("%s", sir);
    for(int i = 0; i < n; ++i) {
        nodes[i + 1].info = 1 << (sir[i] - 97);
    }
    for(int i = 0; i < n - 1; ++i) {
        scanf("%d%d", &x, &y);
        nodes[y].tata = x;
        nodes[y].level = nodes[x].level + 1;
        if(nodes[y].level > h) h = nodes[y].level;
        lista[x] = newNeightboar(y, lista[x]);
    }
    root = 1;
    while(nodes[root].tata) root = nodes[root].tata;
    masks(root, 0);
    for(int i = 0; i < m; ++i) {
        scanf("%d", &t);
        if(t == 2) {
            scanf("%d%s", &x, sir);
            ++n;
            nodes[n].tata = x;
            nodes[n].info = (1 << (sir[0] - 97));
            nodes[n].mask = nodes[x].mask ^ nodes[n].info;
            nodes[n].level = nodes[x].level + 1;
            lista[x] = newNeightboar(n, lista[x]);
            if(nodes[n].level > h) h = nodes[n].level;
        }
        else {
            scanf("%d%d", &x, &y);
            newQuery(x, y);
        }
    }
    computeP(root, sqrt(h));
    while(queries) {
        ans = 0;
        vLca = lca(queries->x, queries->y);
        tans = nodes[queries->x].mask ^ nodes[queries->y].mask ^ nodes[vLca].info;
        while(tans) {
            if(tans & 1) ++ans;
            tans = tans >> 1;
        }
        printf("%d\n", ans);
        queries = queries->next;
    }
}