#include <bits/stdc++.h>
#define inf 2e9
#define all(v) v.begin(), v.end()
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair <int, int> pii;
const int N = 200000 + 3;
int n, q, t[N * 4];
void build(int v, int tl, int tr){
if (tl == tr){
t[v] = inf;
}else{
int tm = (tl + tr) / 2;
build(v * 2, tl, tm);
build(v * 2 + 1, tm + 1, tr);
t[v] = max(t[v * 2], t[v * 2 + 1]);
}
}
int get_min(int v, int tl, int tr, int l, int r){
if (l > r) return inf;
if (tl == l && tr == r){
return t[v];
}
int tm = (tl + tr) / 2;
return min(get_min(v * 2, tl, tm, l, min(r, tm)),
get_min(v * 2 + 1, tm + 1, tr, max(tm + 1, l), r));
}
void up(int v, int tl, int tr, int ind, int val){
if (tl == tr){
t[v] = val;
return;
}
int tm = (tl + tr) / 2;
if (ind <= tm) up(v * 2, tl, tm, ind, val);
else up(v * 2 + 1, tm + 1, tr, ind, val);
t[v] = min(t[v * 2], t[v * 2 + 1]);
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
#ifdef LOCAL
freopen("input.txt", "r", stdin);
#endif // LOCAL
cin >> n >> q;
build(1, 0, n - 1);
while (q--){
char c;
int x, y;
cin >> c >> x >> y;
swap(x, y);
if (c == 'M'){
up(1, 0, n - 1, x - 1, y);
}else{
--x;
int l = x, r = n;
while (l < r){
int mid = (l + r) / 2;
if (get_min(1, 0, n - 1, l, mid) <= y) r = mid;
else l = mid + 1;
}
if (r != n){
cout << r + 1 << "\n";
}else{
cout << -1 << "\n";
}
}
}
}
