Submission #20810

#	Time	Username	Problem	Language	Result	Execution time	Memory
20810		jjwdi0	Crayfish scrivener (IOI12_scrivener)	C++11	60 / 100	1000 ms	96352 KiB

scrivener

int par[1<<20][21], size[1<<20], for_undo[1<<20],  kth, Q;
char a[1<<20];
void Init(){}
void TypeLetter(char x)
{
	for_undo[kth] = kth; if(kth) par[kth][0] = for_undo[kth - 1]; 
	for(int i = 1; par[kth][i-1]; i++)
	{
		par[kth][i] = par[par[kth][i-1]][i-1];
	}
	a[kth] = x, size[kth] = size[par[kth][0]] + 1, kth++;
}
void UndoCommands(int x)
{
	for_undo[kth] = for_undo[kth - x - 1]; kth++;
}
char GetLetter(int x)
{
	int u = for_undo[kth - 1];
	for(int i = 19; i + 1; i--)
	{
		if(size[par[u][i]] > x) u = par[u][i];
	}
	return a[u];
}

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