Submission #707597

#	Time	Username	Problem	Language	Result	Execution time	Memory
707597		Nhoksocqt1	Crayfish scrivener (IOI12_scrivener)	C++17	100 / 100	415 ms	89532 KiB

scrivener

#include<bits/stdc++.h>
using namespace std;

#define inf 0x3f3f3f3f
#define sz(x) int((x).size())
#define fi first
#define se second
typedef long long ll;
typedef pair<int, int> ii;

template<class X, class Y>
	inline bool maximize(X &x, const Y &y) {return (x < y ? x = y, 1 : 0);}
template<class X, class Y>
	inline bool minimize(X &x, const Y &y) {return (x > y ? x = y, 1 : 0);}

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int Random(int l, int r) {
    return uniform_int_distribution<int>(l, r)(rng);
}

const int MAXN = 1000006;

int lastLetter[MAXN], lenOf[MAXN], id[MAXN], P[MAXN][20], numQuery;

void Init(void) {
    numQuery = 0;
    lastLetter[0] = -1;
}

void TypeLetter(char c) {
    ++numQuery;

    id[numQuery] = numQuery;
    lenOf[numQuery] = lenOf[id[numQuery - 1]] + 1;
    P[numQuery][0] = id[numQuery - 1];
    for (int j = 1; j < 20; ++j)
        P[numQuery][j] = P[P[numQuery][j - 1]][j - 1];

    lastLetter[numQuery] = c;
}

void UndoCommands(int U) {
    ++numQuery;
    id[numQuery] = id[numQuery - U - 1];
}

char GetLetter(int T) {
    int x(id[numQuery]);
    for (int i1 = lenOf[x] - T - 1; i1 > 0; i1 ^= i1 & -i1) {
        int i = __builtin_ctz(i1 & -i1);
        x = P[x][i];
    }

    return lastLetter[x];
}

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 22 / 22
• Subtask 4: 26 / 26
• Subtask 5: 40 / 40