#include <cstdio>#include <cstring>#include <algorithm>#include <map>#include <set>#include <bitset>#include <queue>#include <stack>#include <string>#include <iostream>#include <cmath>#include <climits>using namespace std;#define lson rt << 1, l, mid#define rson rt << 1 | 1, mid + 1, rconst int maxn = 1e5 + 10;int head[maxn], nxt[maxn << 1], u[maxn << 1], v[maxn << 1];int tid[maxn], maxson[maxn], siz[maxn], top[maxn], idcnt, ecnt;int lcnt[maxn << 2], lbdc[maxn << 2], rbdc[maxn << 2], lazy[maxn << 2];int n, m, scol[maxn], sval[maxn], dep[maxn], fa[maxn];void init() {	memset(head, -1, sizeof(head));	memset(maxson, -1, sizeof(maxson));	idcnt = ecnt = 0;}void adde(int uu, int vv) {	u[ecnt] = uu; v[ecnt] = vv;	nxt[ecnt] = head[uu]; head[uu] = ecnt++;}void dfs1(int now, int nowfa, int nowdep) {	dep[now] = nowdep; fa[now] = nowfa; siz[now] = 1;	for(int i = head[now]; ~i; i = nxt[i]) if(v[i] != nowfa) {		dfs1(v[i], now, nowdep + 1);		siz[now] += siz[v[i]];		if(maxson[now] == -1 || siz[maxson[now]] < siz[v[i]]) {			maxson[now] = v[i];		}	}}void dfs2(int now, int tp) {	top[now] = tp;	tid[now] = ++idcnt;	if(maxson[now] == -1) return;	dfs2(maxson[now], tp);	for(int i = head[now]; ~i; i = nxt[i]) {		if(v[i] != fa[now] && v[i] != maxson[now]) {			dfs2(v[i], v[i]);		}	}}void pushup(int rt) {	int lc = rt << 1, rc = rt << 1 | 1;	lcnt[rt] = lcnt[lc] + lcnt[rc];	lbdc[rt] = lbdc[lc]; rbdc[rt] = rbdc[rc];	if(rbdc[lc] == lbdc[rc]) lcnt[rt]--;}void fill(int rt, int Col) {	lazy[rt] = Col;	lcnt[rt] = 1;	lbdc[rt] = rbdc[rt] = Col;}void pushdown(int rt) {	if(lazy[rt] == -1) return;	int lc = rt << 1, rc = rt << 1 | 1;	fill(lc, lazy[rt]); fill(rc, lazy[rt]);	lazy[rt] = -1;}void build(int rt, int l, int r) {	lazy[rt] = -1;	if(l == r) {		lcnt[rt] = 1;		lbdc[rt] = rbdc[rt] = sval[l];	}	else {		int mid = (l + r) >> 1;		build(lson); build(rson);		pushup(rt);	}}void update(int rt, int l, int r, int ql, int qr, int Col) {	if(ql <= l && qr >= r) fill(rt, Col);	else {		int mid = (l + r) >> 1;		pushdown(rt);		if(ql <= mid) update(lson, ql, qr, Col);		if(qr > mid) update(rson, ql, qr, Col);		pushup(rt);	}}int query(int rt, int l, int r, int ql, int qr) {	if(ql <= l && qr >= r) return lcnt[rt];	else {		pushdown(rt);		int mid = (l + r) >> 1, ret = 0, lc = rt << 1, rc = rt << 1 | 1;		if(ql <= mid) ret += query(lson, ql, qr);		if(qr > mid) ret += query(rson, ql, qr);		if(ql <= mid && qr > mid && lbdc[rc] == rbdc[lc]) {			ret--;		}		pushup(rt);		return ret;	}}int query_Col(int rt, int l, int r ,int pos) {	if(l == r) return lbdc[rt];	pushdown(rt);	int mid = (l + r) >> 1, ret;	if(pos <= mid) ret = query_Col(lson, pos);	else ret = query_Col(rson, pos);	pushup(rt);	return ret;}int ask(int x, int y) {	int ret = 0;	while(top[x] != top[y]) {		if(dep[top[x]] < dep[top[y]]) swap(x, y);		ret += query(1, 1, idcnt, tid[top[x]], tid[x]);		int ca = query_Col(1, 1, idcnt, tid[top[x]]), 			cb = query_Col(1, 1, idcnt, tid[fa[top[x]]]);		if(ca == cb) ret--;		x = fa[top[x]];	}	if(dep[x] > dep[y]) swap(x, y);	ret += query(1, 1, idcnt, tid[x], tid[y]);	return ret;}void change(int x, int y, int Col) {	while(top[x] != top[y]) {		if(dep[top[x]] < dep[top[y]]) swap(x, y);		update(1, 1, idcnt, tid[top[x]], tid[x], Col);		x = fa[top[x]];	}	if(dep[x] > dep[y]) swap(x, y);	update(1, 1, idcnt, tid[x], tid[y], Col);}int main() {	while(scanf("%d%d", &n, &m) != EOF) {		init();		for(int i = 1; i <= n; i++) scanf("%d", &scol[i]);		for(int i = 1; i < n; i++) {			int a, b; scanf("%d%d", &a, &b);			adde(a, b); adde(b, a);		}		dfs1(1, 1, 1); dfs2(1, 1);		for(int i = 1; i <= n; i++) sval[tid[i]] = scol[i];		build(1, 1, idcnt);		char cmd[10]; int a, b, c;		for(int i = 1; i <= m; i++) {			scanf("%s", cmd);			if(cmd[0] == ‘C‘) {				scanf("%d%d%d", &a, &b, &c);				change(a, b, c);			}			else {				scanf("%d%d", &a, &b);				printf("%d\n", ask(a, b));			}		}	}	return 0;}