Submission #118550

#	Time	Username	Problem	Language	Result	Execution time	Memory
118550		Plurm	Crayfish scrivener (IOI12_scrivener)	C++11	100 / 100	526 ms	154944 KiB

scrivener

#include <vector>
using namespace std;
const int MXN = 1 << 20;
const int COEFF = 18;
char mem[COEFF*MXN];
int llink[COEFF*MXN];
int rlink[COEFF*MXN];
int root;
int nodesz;
vector<int> rootlist;
vector<int> lens;
inline int newnode(int o = -1){
    int c = ++nodesz;
    if(o != -1){
        llink[c] = llink[o];
        rlink[c] = rlink[o];
        mem[c] = mem[o];
    }
    return c;
}
inline int build(int l, int r){
    int c = newnode();
    if(l == r) return c;
    int k = (l+r)/2;
    llink[c] = build(l,k);
    rlink[c] = build(k+1,r);
    return c;
}
inline int update(int o, int idx, char upd, int lb, int rb){
    int nr = newnode(o);
    int b = nr;
    while(lb != rb){
        int k = (lb + rb)/2;
        if(idx <= k){
            rb = k;
            llink[nr] = newnode(llink[nr]);
            nr = llink[nr];
        }else{
            lb = k+1;
            rlink[nr] = newnode(rlink[nr]);
            nr = rlink[nr];
        }
    }
    mem[nr] = upd;
    return b;
}
inline char query(int c, int idx, int lb, int rb){
    while(lb != rb){
        int k = (lb + rb)/2;
        if(idx <= k){
            rb = k;
            c = llink[c];
        }else{
            lb = k+1;
            c = rlink[c];
        }
    }
    return mem[c];
}
void Init() {
    root = build(0, MXN-1);
    rootlist.push_back(root);
    lens.push_back(0);
}
void TypeLetter(char L) {
    int l = lens.back();
    int o = rootlist.back();
    int c = update(o, l, L, 0, MXN-1);
    rootlist.push_back(c);
    lens.push_back(l+1);
}
void UndoCommands(int U) {
    int vn = rootlist.size() - 1 - U;
    lens.push_back(lens[vn]);
    rootlist.push_back(rootlist[vn]);
}
char GetLetter(int P) {
    return query(rootlist.back(), P, 0, MXN-1);
}

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