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#include <cstdlib>
#include <cstdio>
#include <vector>
#include <algorithm>


#include "krazki.h"
#include "message.h"


typedef int smallnum;
typedef long long bignum;


struct node_result {
  int first_ring_position;
  int last_ring_position;
  int airgap;
};

typedef std::vector<smallnum> smallvec;
typedef std::vector<bignum>   bigvec;

void run_master_node(int number_of_nodes) {
  int number_of_workers = number_of_nodes - 1;
  int pipe_height = PipeHeight();
  std::vector<node_result> results(number_of_workers);

  for (int i = 0; i < number_of_workers; i++) {
    int instance_number = Receive(-1);

    results[instance_number-1].airgap = GetInt(instance_number);
    results[instance_number-1].first_ring_position = GetInt(instance_number);
    results[instance_number-1].last_ring_position = GetInt(instance_number);
  }

  int height_so_far = 0;

  for (int i = 0; i < number_of_workers; i++) {
    if (results[i].last_ring_position == 0) {continue;}
    if (results[i].last_ring_position > pipe_height) {
      height_so_far = pipe_height + 1;
      break;
    }

    if (results[i].first_ring_position >= height_so_far) {
      height_so_far = results[i].last_ring_position;
    } else {
      height_so_far = std::max(results[i].last_ring_position,
                                height_so_far + results[i].last_ring_position - results[i].first_ring_position - results[i].airgap);
    }

    if (height_so_far > pipe_height) {
      height_so_far = pipe_height + 1;
      break;
    }
  }

  printf("%d\n", pipe_height - height_so_far + 1);
}


void run_worker_node(int node_id, int number_of_nodes) {
  // Just to avoid overflow
  bignum number_of_discs = NumberOfDiscs();
  bignum pipe_height = PipeHeight();
  bignum worker_id = node_id - 1;
  bignum number_of_workers = number_of_nodes - 1;

  // Choose start and end disc range for this guy
  int start_disc = int(worker_id * number_of_discs / number_of_workers);
  int end_disc = int((worker_id + 1) * number_of_discs / number_of_workers);

  if (end_disc == start_disc) {
    PutInt(0, 0);
    PutInt(0, 0);
    PutInt(0, 0);
    Send(0);
    return;
  }

  // Step 1. Load pipes
  bigvec diameters;
  smallvec pipe_starts;
  smallvec pipe_ends;

  diameters.reserve(pipe_height);
  pipe_starts.reserve(pipe_height);
  pipe_ends.reserve(pipe_height);

  bignum running_min = 0;

  for (smallnum i = 0; i < pipe_height; i++) {
    bignum diameter = HoleDiameter(i+1);

    if (diameters.empty()) {
      running_min = diameter;
      diameters.push_back(diameter);

      pipe_ends.push_back(pipe_height);
      pipe_starts.push_back(pipe_height-1);
    } else {
      if (diameter >= running_min) {
        pipe_starts[pipe_starts.size()-1]--;
      } else {
        running_min = diameter;
        diameters.push_back(diameter);

        pipe_ends.push_back(pipe_height-i);
        pipe_starts.push_back(pipe_height-i-1);
      }
    }
  }

  // Step 2. Load rings
  bignum last_ring_size = -1;
  smallnum last_ring_position = 0;
  smallnum first_ring_position = -1;
  smallnum airgap = 0;

  for (smallnum i = start_disc; i < end_disc; i++) {
    bignum disk_size = DiscDiameter(i+1);

    if (last_ring_size >= disk_size) {
      last_ring_position += 1;
    } else {
      bigvec::reverse_iterator it = std::lower_bound(diameters.rbegin(), diameters.rend(), disk_size);
      smallnum idx = diameters.rend() - it - 1;

      if (idx >= diameters.size()) {
        last_ring_position = pipe_height + 1;
        break;
      }

      smallnum possible_start = pipe_starts[idx];

      if (last_ring_position >= possible_start) {
        last_ring_position += 1;
      } else {
        if (last_ring_position > 0) {
          airgap += (possible_start - last_ring_position);
        }

        last_ring_position = possible_start + 1;
      }

      if (first_ring_position == -1) {
        first_ring_position = last_ring_position - 1;
      }

      if (disk_size > last_ring_size) {
        last_ring_size = disk_size;
      }
    }
  }

  PutInt(0, airgap);
  PutInt(0, first_ring_position);
  PutInt(0, last_ring_position);
  Send(0);
}


int main() {
  int node_id = MyNodeId();

  if (node_id == 0) {
    run_master_node(NumberOfNodes());
    return EXIT_SUCCESS;
  } else {
    run_worker_node(node_id, NumberOfNodes());
    return EXIT_SUCCESS;
  }
}