/*
 _____ _             _              _           _
|_   _| |__   ___   / \   _ __  ___| |__  _   _| |
  | | | '_ \ / _ \ / _ \ | '_ \/ __| '_ \| | | | |
  | | | | | |  __// ___ \| | | \__ \ | | | |_| | |
  |_| |_| |_|\___/_/   \_\_| |_|___/_| |_|\__,_|_|

*/
#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll          int
#define pb          push_back
#define ppb         pop_back
#define	endl		'\n'
#define mii         map<ll,ll>
#define msi         map<string,ll>
#define mis         map<ll, string>
#define rep(i,a,b)    for(ll i=a;i<b;i++)
#define repr(i,a,b) for(ll i=b-1;i>=a;i--)
#define trav(a, x) 	for(auto& a : x)
#define pii         pair<ll,ll>
#define vi          vector<ll>
#define vii         vector<pair<ll, ll>>
#define vs          vector<string>
#define all(a)      (a).begin(),(a).end()
#define F           first
#define S           second
#define sz(x)       (ll)x.size()
#define hell        1000000007
#define lbnd        lower_bound
#define ubnd        upper_bound
#define max(a,b)	(a>b?a:b)
#define min(a,b)	(a<b?a:b)

/*	For Debugging	*/
#define DEBUG 		cerr<<"\n>>>I'm Here<<<\n"<<endl;
#define display(x) trav(a,x) cout<<a<<" ";cout<<endl;
#define what_iss(x)  cerr << #x << " = " << x << endl;
#define what_is(x)  cerr << #x << " = " << x << " ";

std::mt19937_64 rng(std::chrono::steady_clock::now().time_since_epoch().count());
#define ordered_set tree<ll, null_type,less<ll>, rb_tree_tag,tree_order_statistics_node_update>
#define TIME        cerr << "\nTime elapsed: " << setprecision(5) <<1000.0 * clock() / CLOCKS_PER_SEC << "ms\n";
#define DECIMAL(n)  cout << fixed ; cout << setprecision(n);
#define FAST ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
using namespace __gnu_pbds;
using namespace std;
#define PI 3.141592653589793
#define N  100005
ll n,q;
ll srt;
vi v;

class Block {
public:
	vi tmp;
	Block(ll l,ll r) {
		rep(i,l,r+1) {
			tmp.pb(v[i]);
		}
		sort(all(tmp));
	}

	ll query(ll k) {
		return (ll)(ubnd(all(tmp),k) - tmp.begin());
	}
};

vector<Block> blocks;


void preprocess() {
	srt = sqrt(n);
	for(ll i = 0; i < n; i+=srt) {
		blocks.pb(Block(i,min(n - 1,i + srt - 1)));
	}
}


ll manualCalculate(ll l,ll r,ll x) {
	ll cnt = 0;
	rep(i,l,r+1) {
		cnt += (v[i] <= x);
	}
	return cnt;
}

ll findOut(ll l,ll r,ll x) {
	if((l / srt) == (r / srt)) {
		return manualCalculate(l,r,x);
	}

	ll cnt = 0;
	ll L,R;
	L = (l / srt);
	R = (r / srt);
	if(l == L*srt) {
		cnt += blocks[L].query(x);
	} else {
		// what_is(l);
		// what_is(min(n - 1,L * srt + srt - 1));
		// what_iss(manualCalculate(l,min(n - 1,L * srt + srt - 1), x));
		cnt += manualCalculate(l,min(n - 1,L * srt + srt - 1), x);
	}
	if(r == min(n - 1,R * srt + srt - 1)) {
		// what_iss(r);
		// what_iss(blocks[R].query(x));
		cnt += blocks[R].query(x);
	} else {
		cnt += manualCalculate(R * srt, r, x);
	}

	rep(i,L+1,R) {
		cnt+=blocks[i].query(x);
	}
	return cnt;
}

void solve()
{
	cin >> n >> q;
	v.resize(n);
	rep(i,0,n) {
		cin >> v[i];
	}
	preprocess();
	// what_iss(srt);
	char c;
	ll l,r,x;
	ll L,R;
	rep(i,0,q) {
		cin >> c;
		if(c == 'M') {
			cin >> l >> x;
			l --;
			v[l] = x;
			L = (l / srt) * srt;
			blocks[l / srt] = Block(L, min(n - 1, L + srt - 1));
			// what_is(l);
			// what_is(L);
			// what_iss(min(n - 1, L + srt - 1));
		} else {
			cin >> l >> r >> x;
			cout << findOut(l - 1,r - 1,x) << endl;
		}

	}
	return;
}
int main()
{
	FAST
	int TESTS=1;
//	cin>>TESTS;
	rep(i,0,TESTS)
    {
        // cout<<"Case #"<<i+1<<": ";
        solve();
    }
	// TIME
	return 0;
}