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#include <bits/stdc++.h>
// #define int long long

using namespace std;

int lowbit(int x) {
  return x & -x;
}

const int M = 1e7 + 10, N = 1e6 + 10;
set <int> arr[N];
int a[N], lhs[N], lhsq[N], root[N];
struct Node {
  char opt;
  int l, r;
} q[M];

auto findp(int i) {
  return arr[a[i]].upper_bound(i);
}

int find(int i) {
  return *findp(i);
}

auto Findp(int i) {
  return arr[a[i]].lower_bound(i);
}

int Find(int i) {
  return *Findp(i);
}

int n, m, cnt;
int z1[50], z2[50];

struct node {
  int l, r;
  int sum;
  node () {
    l = r = sum = 0;
  }
} z[M];

void qwq() {
  cout << "qwq\n";
}

int query(int ll, int rr) {
  int l = 0, r = n;
  int len1 = 0, len2 = 0;
  for (int i = ll; i; i -= lowbit(i))
    z1[++ len1] = root[i];
  for (int i = rr; i; i -= lowbit(i))
    z2[++ len2] = root[i];
  // qwq();
  int res = 0;
  while (l < r) {
    int mid = l + r >> 1;
    if (rr <= mid) {
      r = mid;
      for (int i = 1; i <= len1; i ++)
        res -= z[z[z1[i]].r].sum;
      // qwq();
      for (int i = 1; i <= len2; i ++)
        res += z[z[z2[i]].r].sum;
      // qwq();
      for (int i = 1; i <= len1; i ++)
        z1[i] = z[z1[i]].l;
      // qwq();
      for (int i = 1; i <= len2; i ++)
        z2[i] = z[z2[i]].l;
      // qwq();
    } else {
      l = mid + 1;
      for (int i = 1; i <= len1; i ++)
        z1[i] = z[z1[i]].r;
      // qwq();
      for (int i = 1; i <= len2; i ++)
        z2[i] = z[z2[i]].r;
      // qwq();
    }
  }
  return res;
}

void modify(int &rt, int l, int r, int k, int c) {
  int fa = rt;
  if (!rt)
    rt = ++ cnt;
  z[rt].l = z[fa].l;
  z[rt].r = z[fa].r;
  z[rt].sum = z[fa].sum + c;
  // cout << z[rt].l << ' ' << z[rt].r << ' ' << z[rt].sum << '\n';
  if (l != r) {
    int mid = l + r >> 1;
    if (k <= mid)
      modify(z[rt].l, l, mid, k, c);
    else
      modify(z[rt].r, mid + 1, r, k, c);
  }
}

void modify(int x, int k, int c) {
  for (int i = x; i <= n; i += lowbit(i))
    modify(root[i], 0, n, k, c);
}

int nn;

int get(int x) {
  int l = 1, r = nn;
  while (l < r) {
    int mid = l + r >> 1;
    if (x <= lhs[mid])
      r = mid;
    else
      l = mid + 1;
  }
  return l;
}

signed main() {
  cin >> n >> m;
  for (int i = 0; i < N; i ++)
    arr[i].insert(0);
  for (int i = 0; i < N; i ++)
    arr[i].insert(n + 1);
  for (int i = 1; i <= n; i ++)
    cin >> a[i];
  for (int i = 1; i <= m; i ++)
    cin >> q[i].opt >> q[i].l >> q[i].r;
  int tot = 0;
  for (int i = 1; i <= n; i ++)
    lhsq[++ tot] = a[i];
  for (int i = 1; i <= m; i ++)
    if (q[i].opt != 'Q')
      lhsq[++ tot] = q[i].r;
  sort (lhsq + 1, lhsq + tot + 1);
  lhs[nn = 1] = lhsq[1];
  for (int i = 2; i <= tot; i ++)
    if (lhsq[i] != lhsq[i - 1])
      lhs[++ nn] = lhsq[i];
  for (int i = 1; i <= n; i ++)
    a[i] = get(a[i]);
  for (int i = 1; i <= n; i ++)
    arr[a[i]].insert(i);
  n ++;
  for (int i = 1; i < n; i ++)
    modify(i, find(i), 1);
  for (int i = 1; i <= m; i ++) {
    int l = q[i].l, r = q[i].r;
    char &opt = q[i].opt;
    if (opt == 'Q')
      cout << query(l - 1, r) << '\n';
    else {
      auto p = prev(Findp(l));
      int t = *p;
      if (t) {
        modify(t, l, -1);
        modify(t, find(l), 1);
      }
      modify(l, find(l), -1);
      arr[a[l]].erase(l);
      a[l] = get(q[i].r);
      arr[a[l]].insert(l);
      p = prev(Findp(l));
      t = *p;
      if (t) {
        modify(t, l, 1);
        modify(t, find(l), -1);
      }
      modify(l, find(l), 1);
    }
  }
  return 0;
}