Cod sursa(job #1469195)

Utilizator MarcvsHdrMihai Leonte MarcvsHdr Data 7 august 2015 18:09:54
Problema Order Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.97 kb
#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

struct Elimin {
  vector<int> aib;
  int n;

  Elimin(int n) : n(n), aib(n + 1) { }

  inline void add(int pos) {
    while (pos <= n) {
      aib[pos]++;
      pos += pos ^ (pos & (pos - 1));
    }
  }

  inline int ask1(int pos) {
    int sol = 0;
    while (pos) {
      sol += aib[pos];
      pos = pos & (pos - 1);
    }
    return sol;
  }

  inline int wrap(int start, int tostep) {
    if (start + tostep <= n) {
      return start + tostep;
    } else {
      int sol = (tostep - (n - start)) % n;
      return sol == 0 ? n : sol;
    }
  }

  int ask_wrap(int start, int step) {
    if (start + step <= n) {
      return ask1(start + step) - ask1(start);
      //return ask(start + 1, start + step);
    } else {
      int full_laps = (step - (n - start)) / n;
      int left = (step - (n - start)) % n;
      return
          ask1(n) - ask1(start) +
          full_laps * ask1(n) +
          (left > 0 ? ask1(left) : 0);
    }
  }

  int find_advance(int start, int tostep) {
    // We need to find a step such that step - ask_wrap(start, step) == tostep
    int li = tostep;
    int lf = n * (1 + tostep / (n - tostep + 1));
    int minsol = 0, m;
    while (li <= lf) {
      m = (li + lf) / 2;
      int realstep = m - ask_wrap(start, m);
      //std::cerr << "realstep(" << start << " + " << m << ") = " << realstep << std::endl;
      if (realstep == tostep) {
        minsol = m;
        lf = m - 1;
      } else if (realstep > tostep) {
        lf = m - 1;
      } else {
        li = m + 1;
      }
    }

    //std::cerr << "Retuning " << wrap(start, minsol) << std::endl;
    return wrap(start, minsol);
  }
};

int n, p, step;

int main()
{
  ifstream in("order.in");
  in >> n;
  in.close();
  Elimin e(n);

  ofstream out("order.out");
  for (p = 1, step = 1; step <= n; ++step) {
    p = e.find_advance(p, step);
    e.add(p);
    out << (step > 1 ? " " : "") << p;
  }

  out << "\n";
  out.close();

  return 0;
}