#include <bits/stdc++.h>
using namespace std;
#define pii pair<long long, long long >
#define F first
#define S second
#define mp make_pair
pair<pii, pii > a[200005];
long long ans[200005];
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
//freopen("output.txt", "w", stdout);
//if(fopen(".inp", "r")) freopen(".inp", "r", stdin);
long long n, Q; cin >> n >> Q;
for(long long i=1 ; i<=Q ; ++i) {
char c; cin >> c;
long long A, B; cin >> A >> B;
if(c=='M') a[i] = mp( mp(A, 0), mp(B, 0) );
else a[i] = mp( mp(A, 1), mp(B, i ) );
}
set <long long > s;
sort(a+1, a+Q+1);
for(long long i=1; i<=Q ; ++i) {
if(a[i].F.S==0) s.insert(a[i].S.F);
else {
auto id = s.lower_bound(a[i].S.F);
if(id==s.end()) ans[a[i].S.S]=-1;
else ans[a[i].S.S]=*id;
}
}
for(long long i=1 ; i<=Q ; ++i) {
if(ans[i]) cout << ans[i] << '\n';
}
return 0;
}
