Submission #225710

#	Time	Username	Problem	Language	Result	Execution time	Memory
225710		spdskatr	Crayfish scrivener (IOI12_scrivener)	C++14	100 / 100	535 ms	74976 KiB

scrivener

#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <vector>

using namespace std;

int cnt = 1, cur = 0, jp[1000005][21], depth[1000005];
struct node {
	char val;
	int par;
} tree[1000005];

vector<int> pos;

void Init() { /* lol who inits amirite */ }

void TypeLetter(char L) {
	tree[cnt] = { L, cur };
	jp[cnt][0] = cur;
	depth[cnt] = depth[cur] + 1;
	cur = cnt;
	for (int k = 1; k <= 20; k++) jp[cur][k] = jp[jp[cur][k-1]][k-1];
	pos.push_back(cur);
	cnt++;
}

void UndoCommands(int U) {
	int nd = pos[pos.size() - 1 - U];
	cur = nd;
	pos.push_back(cur);
}

char GetLetter(int P) {
	int x = depth[cur] - P - 1;
	int c = cur;
	for (int k = 20; k >= 0; k--) {
		if ((x >> k) & 1) c = jp[c][k];
	}
	return tree[c].val;
}

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