Submission #1617

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
1617	2013-07-10T15:11:39 Z	tncks0121	Crayfish scrivener (IOI12_scrivener)	C++	Compilation error	0 ms	0 KB

scrivener

const int MAXC = 1000005;
const int lgMAXC = 20;
 
struct node{
    char letter;
    int level;
    node* parent[lgMAXC];
 
    node(char letter, node* par): letter(letter){
        parent[0] = par; 
        if(par != NULL) level = par->level + 1; else level = 0;
        for(int i=1; i<lgMAXC; i++){
            if(parent[i-1] == NULL) parent[i] = NULL;
            else parent[i] = parent[i-1]->parent[i-1];
        }
    }
};
 
node* Commands[MAXC];
node* now;
int N;
 
void Init(){
    now = new node(0, NULL);
    Commands[1] = now; N = 1;
}
 
void TypeLetter(char L){
    Commands[++N] = new node(L, now);
    now = Commands[N];
}
 
void UndoCommands(unsigned int U){
    int val = N - U; Commands[++N] = Commands[val];
    now = Commands[N];
}
 
char GetLetter(unsigned int P){
    node* tmp = now; int L = now->level - P;
    for(int i=0; (1<<i)<=L; i++) if(L & (1<<i)){
        tmp = tmp->parent[i];
    }
    return tmp->letter;
}

Compilation message

scrivener.cpp: In constructor 'node::node(char, node*)':
scrivener.cpp:11: error: 'NULL' was not declared in this scope
scrivener.cpp:13: error: 'NULL' was not declared in this scope
scrivener.cpp: In function 'void Init()':
scrivener.cpp:24: error: 'NULL' was not declared in this scope