Submission #120480

#	Time	Username	Problem	Language	Result	Execution time	Memory
120480		KieranHorgan	Crayfish scrivener (IOI12_scrivener)	C++17	100 / 100	822 ms	89552 KiB

scrivener

#include <bits/stdc++.h>
using namespace std;
int a[1000005][23];
int curStep=0, node, i;
void Init() {}
void TypeLetter(char L) {
	a[++curStep][21] = L;
	a[curStep][22] = a[curStep-1][22]+1;
	a[curStep][0] = curStep-1;
	for(i = 1; 1<<i <= a[curStep][22]; i++)
		a[curStep][i] = a[a[curStep][i-1]][i-1];
}

void UndoCommands(int U) {
	copy(a[curStep-1-U], a[curStep-1-U]+23, a[++curStep]);
}

char GetLetter(int P) {
  for(i = 21, node = curStep; i >= 0; i--)
  	if(a[node][22] - (1<<i) >= P+1)
  		node = a[node][i];
  return a[node][21];
}

Compilation message (stderr)

scrivener.cpp: In function 'void UndoCommands(int)':
scrivener.cpp:15:44: warning: operation on 'curStep' may be undefined [-Wsequence-point]
  copy(a[curStep-1-U], a[curStep-1-U]+23, a[++curStep]);
                                            ^~~~~~~~~
scrivener.cpp:15:44: warning: operation on 'curStep' may be undefined [-Wsequence-point]

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