#include <bits/stdc++.h>
using ll = long long;
using namespace std;
const int INF = 1e9;
vector<int> t;
void build(const vector<int>& a, int v, int tl, int tr)
{
if (tl==tr) t[v]=a[tl];
else{
int tm = (tl+tr)/2;
build(a, v*2, tl, tm);
build(a, v*2+1, tm+1, tr);
t[v] = min(t[v*2], t[v*2+1]);
}
}
int query(int v, int tl, int tr, int l, int r, int Y)
{
if (l>r) return -1;
if (t[v] > Y) return -1;
if (tl == tr) return tl;
int tm = (tl+tr)/2;
if (l <= tm) {
int left_res = query(v*2, tl, tm, l, min(r, tm), Y);
if (left_res != -1) return left_res;
}
if (r > tm) {
int right_res = query(v*2+1, tm+1, tr, max(l, tm+1), r, Y);
if (right_res != -1) return right_res;
}
return -1;
}
void update(int v, int tl, int tr,int pos, int new_val)
{
if (tl == tr) t[v] = new_val;
else{
int tm = (tl+tr)/2;
if (pos<=tm) update(v*2, tl, tm, pos, new_val);
else update(v*2+1, tm+1, tr, pos, new_val);
t[v] = min(t[v*2], t[v*2+1]);
}
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int N, M;
cin >> N >> M;
t.assign(4*N, 0);
vector<int> a(N+1);
for (int i=1; i<=N; i++) a[i] = INF;
build(a,1,1,N);
for (int i = 0; i<M; i++)
{
char op;
cin >> op;
if (op == 'M'){
int X, A;
cin >> X >> A;
update(1,1,N,A,X);
}
else{
int Y, B;
cin >> Y >> B;
cout << query(1, 1, N, B, N, Y) << '\n';
}
}
}
