#include <bits/stdc++.h>
using namespace std;
#define pb push_back
const int maxn = 2e5 + 10, inf = 1e9 + 7;
int n, q, ar[maxn], seg[maxn << 2];
void input() {
cin >> n >> q;
fill(ar,ar + maxn,inf);
fill(seg,seg + (maxn << 2),inf);
n++;
}
void upd(int p, int x,int id = 1,int st = 1, int en = n) {
if (st > p || en <= p)
return;
seg[id] = min(seg[id],x);
if ((en - st) == 1)
return;
int lc = id << 1, rc = id << 1 | 1, mid = (st + en) >> 1;
upd(p,x,lc,st,mid),upd(p,x,rc,mid,en);
}
int get(int l, int r,int id = 1,int st = 1, int en = n) {
int lc = id << 1, rc = id << 1 | 1, mid = (st + en) >> 1;
if (st >= r || en <= l)
return inf;
if (st >= l && en <= r)
return seg[id];
return min(get(l,r,lc,st,mid),get(l,r,rc,mid,en));
}
int main() {
ios_base:: sync_with_stdio(0), cin.tie(0), cout.tie(0);
input();
while (q--) {
char type;
cin >> type;
if (type == 'M') {
int x, p;
cin >> x >> p;
upd(p,x);
ar[p] = x;
}
else {
int y, l;
cin >> y >> l;
if (ar[l] <= y)
cout << l << "\n";
else if (get(l,n) > y)
cout << -1 << "\n";
else {
int r = n;
while (r - l > 1) {
int mid = (r + l) / 2;
if (get(l,mid) <= y)
r = mid;
else
l = mid;
}
cout << l << "\n";
}
}
}
}
