Submission #302865

#	Time	Username	Problem	Language	Result	Execution time	Memory
302865		Hehehe	Crayfish scrivener (IOI12_scrivener)	C++14	100 / 100	721 ms	116728 KiB

scrivener

#include<bits/stdc++.h> //:3
using namespace std;
typedef long long ll;
#define all(a) (a).begin(), (a).end()
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define pi pair<int, int>
#define sz(x) (int)((x).size())
//#define int long long

const int dx[] = {0, 1, 0, -1};
const int dy[] = {1, 0, -1, 0};

const ll inf = 2e9;
const ll mod = 1e9 + 7;
const int N = 1e6 + 11;
const ll INF64 = 3e18 + 1;
const double eps = 1e-14;
const double PI = acos(-1);

//ifstream in(".in");
//ofstream out(".out");

int v[N], tip[N], p[N], lvl[N], dp[N][25], k;

void Init(){};

void TypeLetter(char L){

    int nod = v[k];
    v[++k] = k;

    tip[k] = L - 'a';

    if(tip[nod] == -1){
        p[k] = p[nod];
    }else{
        p[k] = nod;
    }

    lvl[k] = lvl[p[k]] + 1;

    dp[k][0] = p[k];
    for(int i = 1; i <= 20; i++){
        dp[k][i] = dp[dp[k][i - 1]][i - 1];
    }
}

void UndoCommands(int U){

    int nod = v[k - U];
    v[++k] = k;

    tip[k] = -1;

    if(tip[nod] == -1){
        p[k] = p[nod];
    }else{
        p[k] = nod;
    }
}

char GetLetter(int P){

    int nod = v[k];
    if(tip[nod] == -1)nod = p[nod];

    int len = lvl[nod] - P - 1;
    for(int i = 20; i >= 0; i--){
        if((1 << i) <= len){
            nod = dp[nod][i];
            len -= (1 << i);
        }
    }

    return (char)(tip[nod] + 'a');
}

Compilation message (stderr)

scrivener.cpp: In function 'void TypeLetter(char)':
scrivener.cpp:33:7: warning: operation on 'k' may be undefined [-Wsequence-point]
   33 |     v[++k] = k;
      |       ^~~
scrivener.cpp:33:7: warning: operation on 'k' may be undefined [-Wsequence-point]
scrivener.cpp: In function 'void UndoCommands(int)':
scrivener.cpp:54:7: warning: operation on 'k' may be undefined [-Wsequence-point]
   54 |     v[++k] = k;
      |       ^~~
scrivener.cpp:54:7: warning: operation on 'k' 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