#include <iostream>#include <cstdlib>#include <cstdio>#include <cstring>#include <cmath>#include <algorithm>using namespace std;const int MaxN = 100000 + 5;int n, m, Index;int Father[MaxN], Son[MaxN], Depth[MaxN], Top[MaxN], A[MaxN], Size[MaxN], Pos[MaxN];int Color[MaxN];struct Edge{	int v;	Edge *Next;} E[MaxN * 2], *P = E, *Point[MaxN];inline void AddEdge(int x, int y) {	++P; P -> v = y;	P -> Next = Point[x]; Point[x] = P;}int DFS_1(int x, int Dep, int Fa) {	Depth[x] = Dep; 	Father[x] = Fa;	Size[x] = 1;	int SonSize, MaxSonSize;	SonSize = MaxSonSize = 0;	for (Edge *j = Point[x]; j; j = j -> Next) {		if (j -> v == Fa) continue;		SonSize = DFS_1(j -> v, Dep + 1, x);		if (SonSize > MaxSonSize) {			Son[x] = j -> v;			MaxSonSize = SonSize;		}		Size[x] += SonSize;	}	return Size[x];}void DFS_2(int x) {	if (x == 0) return;	if (x == Son[Father[x]]) Top[x] = Top[Father[x]];	else Top[x] = x;	Pos[x] = ++Index;	Color[Pos[x]] = A[x];	DFS_2(Son[x]);	for (Edge *j = Point[x]; j; j = j -> Next) {		if (j -> v == Father[x] || j -> v == Son[x]) continue;		DFS_2(j -> v);	}}struct ES {	int Lx, Rx, Tx;	ES() {}	ES(int a, int b, int c) {		Lx = a; Rx = b; Tx = c;	}} T[MaxN * 4], D[MaxN * 4];ES Plus(ES e1, ES e2) {	ES ret;	if (e1.Tx == 0) return e2;	if (e2.Tx == 0) return e1;	ret = ES(e1.Lx, e2.Rx, e1.Tx + e2.Tx);	if (e1.Rx == e2.Lx) --ret.Tx;	return ret;}inline void Update(int x) {	T[x] = Plus(T[x << 1], T[x << 1 | 1]);}void Plant_Tree(int x, int s, int t) {	if (s == t) {		T[x] = ES(Color[s], Color[s], 1);		D[x] = ES(0, 0, 0);		return;	}	int m = (s + t) >> 1;	Plant_Tree(x << 1, s, m);	Plant_Tree(x << 1 | 1, m + 1, t);	Update(x);}inline void Paint(int x, ES Dlt) {	T[x] = Dlt;	D[x] = Dlt;}inline void PushDown(int x) {	if (D[x].Tx == 0) return;	Paint(x << 1, D[x]);	Paint(x << 1 | 1, D[x]);	D[x] = ES(0, 0, 0);}void Change_Tree(int x, int s, int t, int l, int r, int Col) {	if (l <= s && r >= t) {		ES Temp = ES(Col, Col, 1);		Paint(x, Temp);		return;		}	PushDown(x);	int m = (s + t) >> 1;	if (l <= m) Change_Tree(x << 1, s, m, l, r, Col);	if (r >= m + 1) Change_Tree(x << 1 | 1, m + 1, t, l, r, Col);	Update(x);}void Change_Color(int x, int y, int z) {	int fx, fy;	while (true) {		fx = Top[x]; fy = Top[y];		if (Depth[fx] < Depth[fy]) {			swap(fx, fy);			swap(x, y);		}		if (fx == fy) {			if (Pos[x] < Pos[y]) Change_Tree(1, 1, n, Pos[x], Pos[y], z);			else Change_Tree(1, 1, n, Pos[y], Pos[x], z);			break;		}		else {			Change_Tree(1, 1, n, Pos[fx], Pos[x], z);			x = Father[fx];		}	}}ES Query_Tree(int x, int s, int t, int l, int r) {	if (l <= s && r >= t) return T[x];	PushDown(x);	int m = (s + t) >> 1;	ES ret = ES(0, 0, 0);	if (l <= m) ret = Plus(ret, Query_Tree(x << 1, s, m, l, r)); 	if (r >= m + 1) ret = Plus(ret, Query_Tree(x << 1 | 1, m + 1, t, l, r));	return ret;}int Query(int x, int y) {	int fx, fy, ret;	ES Ansx, Ansy, Temp;	Ansx = Ansy = ES(0, 0, 0);	while (true) {		fx = Top[x]; fy = Top[y];		if (Depth[fx] < Depth[fy]) {			swap(fx, fy);			swap(x, y);			swap(Ansx, Ansy);		}		if (fx == fy) {			ret = Ansx.Tx + Ansy.Tx;			if (Pos[x] < Pos[y]) {				Temp = Query_Tree(1, 1, n, Pos[x], Pos[y]);				ret += Temp.Tx;				if (Ansy.Lx == Temp.Rx) --ret;				if (Ansx.Lx == Temp.Lx) --ret;			}			else {				Temp = Query_Tree(1, 1, n, Pos[y], Pos[x]);				ret += Temp.Tx;				if (Ansx.Lx == Temp.Rx) --ret;				if (Ansy.Lx == Temp.Lx) --ret;			}			break;		}		else {			Ansx = Plus(Query_Tree(1, 1, n, Pos[fx], Pos[x]), Ansx);			x = Father[fx];		}	}	return ret;}int main() {	scanf("%d%d", &n, &m);	for (int i = 1; i <= n; ++i) scanf("%d", &A[i]);	int a, b, c;	for (int i = 1; i <= n - 1; ++i) {		scanf("%d%d", &a, &b);		AddEdge(a, b);		AddEdge(b, a);	}	DFS_1(1, 0, 0);	Index = 0;	DFS_2(1);	Plant_Tree(1, 1, n);	char ch;	int Ans;	for (int i = 1; i <= m; ++i) {		ch = ‘#‘;		while (ch != ‘C‘ && ch != ‘Q‘) ch = getchar();		if (ch == ‘C‘) {			scanf("%d%d%d", &a, &b, &c);			Change_Color(a, b, c);		}		else {			scanf("%d%d", &a, &b);			Ans = Query(a, b);			printf("%d\n", Ans);		}	}	return 0;}