Submission #237347

#	Time	Username	Problem	Language	Result	Execution time	Memory
237347		T0p_	Crayfish scrivener (IOI12_scrivener)	C++14	100 / 100	520 ms	207348 KiB

scrivener

#include <bits/stdc++.h>
using namespace std;
 
struct node
{
	int l, r;
	char c;
};
 
int all, ver;
int root[1000005], heigh[1000005];
node seg[23000000];
 
int build(int l, int r)
{
	int now = ++all;
	if(l == r) return now;
	int mid = (l+r)>>1;
	int L = build(l, mid), R = build(mid+1, r);
	seg[now].l = L, seg[now].r = R;
	return now;
}
 
void Init() {
	root[0] = build(1, 1000000);
}
 
int update(int idx, int l, int r, int p, char c) {
	if(!(l <= p && p <= r)) return idx;
	int now = ++all;
	if(l == r)
	{
		seg[now].c = c;
		return now;
	}
	int mid = (l+r)>>1;
	int L = update(seg[idx].l, l, mid, p, c), R = update(seg[idx].r, mid+1, r, p, c);
	seg[now].l = L, seg[now].r = R;
	return now;
}
 
void TypeLetter(char L) {
	ver++;
	heigh[ver] = heigh[ver-1]+1;
	root[ver] = update(root[ver-1], 1, 1000000, heigh[ver], L);
}
 
void UndoCommands(int U) {
	ver++;
	heigh[ver] = heigh[ver-U-1];
	root[ver] = root[ver-U-1];
}
 
char query(int idx, int l, int r, int p)
{
	if(l == r) return seg[idx].c;
	int mid = (l+r)>>1;
	return (p <= mid) ? query(seg[idx].l, l, mid, p) : query(seg[idx].r, mid+1, r, p);
}
 
char GetLetter(int P) {
	return query(root[ver], 1, 1000000, P+1);
}

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