Submission #1187924

#	Time	Username	Problem	Language	Result	Execution time	Memory
1187924		lance0	Crayfish scrivener (IOI12_scrivener)	C++20	100 / 100	410 ms	223620 KiB

scrivener

#include <ext/rope>
__gnu_cxx::crope ver[1000010]; //set up all versions with rope data struct
int curr_ver = 0; //and track version number
void Init(){}
void TypeLetter(char L) {
	//newest version is just previous version + new char
	curr_ver++;
	ver[curr_ver] = ver[curr_ver-1] + L;
}

void UndoCommands(int U) {
	//using the fact undos are just jumps to U steps back, newest version = U steps back from last version
	curr_ver++;
	ver[curr_ver] = ver[curr_ver-1-U];
}

char GetLetter (int P) {
	//Pth letter is simply current version's Pth letter
	return ver[curr_ver][P];
}

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