This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
typedef long long       ll;
typedef pair<ll, ll>    pll;
typedef pair<int, int>  pii;
#define all(x)          x.begin(), x.end()
#define kill(x)         return cout << x << endl, 0
#define X               first
#define Y               second
//#define endl            '\n'
constexpr ll pw(ll a, ll b, ll mod) {
    return (!b    ? 1 :
            b & 1 ? a * pw(a * a % mod, b / 2, mod) % mod :
                    pw(a * a % mod, b / 2, mod));
}
constexpr int N   = 1e6 + 10;
constexpr int MOD = 1e9 + 7;
constexpr ll INF  = 1e18;
int cur, par[N], prv[N], sz[N];
char C[N];
string ans;
void Init() {
    
}
void TypeLetter(char L) {
    cur++;
    C[cur] = L;
    par[cur] = cur - 1;
    prv[cur] = cur;
    sz[cur] = sz[par[cur]] + 1;
}
void UndoCommands(int U) {
    cur++;
    C[cur] = 'U';
    par[cur] = cur - U - 1;
    prv[cur] = prv[par[cur]];
    sz[cur] = sz[par[cur]];
}
char GetLetter(int P) {
    if (true || ans.size() != sz[cur]) {
        for (int tmp = prv[cur]; tmp > 0; tmp = prv[par[tmp]]) {
            ans.push_back(C[tmp]);
            //cerr << tmp << ' ' << par[tmp] << endl;
        }
        reverse(all(ans));
    }
    return ans[P];
}
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