#define _CRT_SECURE_NO_DEPRECATE

#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <utility>
#include <cstdlib>
using namespace std;

#define  DMAX 100002

int n, m;
string s;
vector <pair<char, vector<int> > > T;
vector <int> parent;

void BFS(int root){
	int i, chld;
	queue<int> Q;
	Q.push(root);

	while (Q.size()){
		root = Q.front(); Q.pop();
		for ( i = T[root].second.size() - 1; i >= 0; i--){
			chld = T[root].second[i];
			parent[chld] = root;
			Q.push(chld);
		}
	}
}

string getpath(int x, int y){
	string p;

	parent.insert(parent.begin(), 0, T.size() + 1);

	BFS(x);

	while (parent[y] != x){
		p += T[y].first;
		y = parent[y];
	}

	return p;
}

void solve(int x, int y){
	int i, c = 0;
	string p = getpath(x, y);
	vector<int> a(26);

	for (i = s.size() - 1; i >= 0; i--){
		a[s[i] - 'a']++;
	}
	
	for ( i = 0; i < 26; i++){
		if (a[i] % 2) c++;
	}

	cout << c << '\n';
}

int main(){
	int i, x, y;

	//freopen("test.in", "r", stdin);
	//freopen("test.out", "w", stdout);

	cin >> n >> m >> s;

	T.push_back({ 'c', {}});

	for ( i = 0; i < n; i++) 
		T.push_back({ s[i], {} });

	for ( i = 1; i < n; i++){
		cin >> x >> y;
		T[x].second.push_back(y);
		T[y].second.push_back(x);
	}

	for ( i = 0; i < m; i++){
		cin >> x;
		if(x == 1){
			cin >> x >> y;
			solve(x, y);
		}
		else{
			cin >> x >> y;
			T.push_back({ (char)y - 'a', {} });
			T[x].second.push_back(T.size());
			T[T.size()].second.push_back(x);
		}
	}

	return 0;
}