Submission #95557

#	Time	Username	Problem	Language	Result	Execution time	Memory
95557		oolimry	Crayfish scrivener (IOI12_scrivener)	C++14	100 / 100	636 ms	72820 KiB

scrivener

#include <bits/stdc++.h>
int p[1000005][22];
char character[1000005];
int point[1000005];
int depth[1000005];
int x = 0;
int cur = 0;
int mcur = 0;
void Init() {
    for(int i = 0;i < 22;i++)
        p[0][i] = -1;
    depth[0] = 0;
}
void TypeLetter(char L) {
    int next = mcur + 1;
    point[x] = next;
    character[next] = L;
    depth[next] = depth[cur] + 1;
    p[next][0] = cur;
    for(int i = 1;i < 22;i++){
        if(p[next][i-1] != -1) p[next][i] = p[p[next][i-1]][i-1];
        else {p[next][i] = -1; continue;}
    }
    cur = next;
    mcur++;
    x++;
}
void UndoCommands(int U) {
    cur  = point[x - U - 1];
    point[x] = cur;
    x++;
}
char GetLetter(int P) {
    int k = depth[cur] - P - 1;
    int node = cur;
    while(k > 0){
        int kk = (k & (-k));
        k -= kk;
        kk = log2(kk);
        node = p[node][kk];
    }
    return character[node];
}

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