#include <bits/stdc++.h>
using namespace std;
const int nx = 2e5 + 5;
int n, q;
int tree[4*nx];
void update(int idx, int l, int r, int x, int val) {
if (r < x || x < l) return;
if (l == r) {
tree[idx] = val;
return;
}
int mid = (l + r) >> 1;
update(idx*2, l, mid, x, val);
update(idx*2+1, mid + 1, r, x, val);
tree[idx] = min(tree[idx*2], tree[idx*2+1]);
return;
}
int query(int idx, int l, int r, int a, int b) {
if (r < a || l > b) return 2e9;
if (a <= l && r <= b) return tree[idx];
int mid = (l + r) >> 1;
return min(query(idx*2, l, mid, a, b), query(idx*2+1, mid + 1, r, a, b));
}
int main() {
ios_base::sync_with_stdio(0), cin.tie(0);
cin >> n >> q;
for (int i = 1; i <= n + 1; i++) {
update(1, 1, n + 1, i, 2e9);
}
while (q--) {
char op; cin >> op;
if (op == 'M') {
int x, a;
cin >> x >> a;
update(1, 1, n + 1, a, x);
continue;
}
int y, b;
cin >> y >> b;
int l = b, r = n + 1;
while (l < r) {
int mid = (l + r) >> 1;
if (query(1, 1, n + 1, b, mid) <= y) {
r = mid;
} else {
l = mid + 1;
}
}
if (l == n + 1) {
cout << -1 << "\n";
} else {
cout << l << "\n";
}
}
}
