#include <bits/stdc++.h>
using namespace std;
const int N = 1e6;
int read() {
	int s = 0, w = 1;
	char c = getchar();
	while (c < '0' || c > '9') {
		if (c == '-') w = -1;
		c = getchar();
	}
	while (c >= '0' && c <= '9') { 
		s = s * 10 + c - '0';
		c = getchar();
	}
	return s * w;
}
void print(int x) {
	if (x < 0) { //判负
		putchar('-');
		x = -x;
	}
	if (x >= 10)
		print(x / 10);
	putchar(x % 10 + '0');
	return;
}
struct node {
	int L, R, K;
} q[N];
int pos[N], ans[N], cnt[N], a[N];
bool cmp(node a, node b) {
	if (pos[a.L] != pos[b.L]) {
		return pos[a.L] < pos[b.L];
	}
	if (pos[a.L] & 1) return a.R > b.R;
	return a.R < b.R;
}
int ANS = 0;
void add(int x) {
	cnt[a[x]]++;
	if (cnt[a[x]] == 1) ANS++;
}
void del(int x) {
	cnt[a[x]]--;
	if (cnt[a[x]] == 0) ANS--;
}
int main() {
	int n = read(),m = read();
	int block = sqrt(n);
	for (int i = 1; i <= n; i++) {
		a[i] = read();
		pos[i] = (i - 1) / block + 1;
	}
	for (int i = 1; i <= m; i++) {
		char opr;
		cin >> opr;
		if(opr == 'Q')
		{
			q[i].L = read();
			q[i].R = read();
			q[i].K = i;		
		}
		else
		{
			int x,k;
			cin >> x >> k;
			a[x] = k;
		}
	}
	sort(q + 1, q + 1 + m, cmp);
	int L = 1, R = 0;
	for (int i = 1; i <= m; i++) {
		while (L < q[i].L) del(L++);
		while (R > q[i].R) del(R--);
		while (L > q[i].L) add(--L);
		while (R < q[i].R) add(++R);
		ans[q[i].K] = ANS;
	}
	for (int i = 1; i <= m; i++) {
		print(ans[i]);
		puts("");
	}
}

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