#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define int ll
#define all(x) x.begin(), x.end()
#define x first
#define y second
#define mp make_pair
#define mt make_tuple
const int N = 1 << 18;
const int INF = 1e18;
int n;
int q;
int t[2 * N];
void upd(int i, int v) {
t[i += N] = v;
for (i /= 2; i > 0; i /= 2) {
t[i] = min(t[i + i], t[i + i + 1]);
}
}
int query(int l, int r) {
int mn = INF;
for (l += N, r += N; l <= r; l /= 2, r /= 2) {
if (l % 2 == 1) {
mn = min(mn, t[l++]);
}
if (r % 2 == 0) {
mn = min(mn, t[r--]);
}
}
return mn;
}
signed main() {
#ifdef LC
assert(freopen("input.txt", "r", stdin));
#endif
ios::sync_with_stdio(0);
cin.tie(0);
fill_n(t, 2 * N, INF);
cin >> n >> q;
while (q--) {
char tp;
cin >> tp;
if (tp == 'M') {
int x;
int y;
cin >> y >> x;
upd(x, y);
} else {
int x;
int y;
cin >> y >> x;
if (query(x, n) > y) {
cout << "-1\n";
continue;
}
int lef = x - 1, rig = n;
while (rig - lef > 1) {
int mid = (lef + rig) / 2;
if (query(x, mid) <= y) {
rig = mid;
} else {
lef = mid;
}
}
cout << rig << "\n";
}
}
return 0;
}
