Submission #7278

#	Time	Username	Problem	Language	Result	Execution time	Memory
7278		kriii	Crayfish scrivener (IOI12_scrivener)	C++98	0 / 100	520 ms	166800 KiB

scrivener

#include <vector>
#include <map>
using namespace std;

map<char, int> trie[1000001]; int prv[1000001][20];
int node,now,time,hist[1000001]; char get[10000001];

void Init() {}

void TypeLetter(char L) {
	int &n = trie[now][L];
	if (n == 0){
		n = ++node;
		prv[n][0] = now;
		for (int i=1;i<20;i++) prv[n][i] = prv[prv[n][i-1]][i-1];
		get[n] = L;
	}
	hist[++time] = now = n;
}

void UndoCommands(int U) {
	now = hist[time-U];
	hist[++time] = now;
}

char GetLetter(int P) {
	int x = now; P--;
	for (int i=0;i<20;i++) if (P & (1 << i)) x = prv[x][i];
	return get[x];
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 7
• Subtask 3: 0 / 22
• Subtask 4: 0 / 26
• Subtask 5: 0 / 40