1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
#include  "krazki.h"
#include "message.h"
#include <iostream>

int main(int argc, char** argv) {
	int number_of_nodes = NumberOfNodes();
	int my_node = MyNodeId();
	int pipe_height = PipeHeight();
	int number_of_discs = NumberOfDiscs();

	if (pipe_height < pipe_height) {
		if (my_node == 0) {
			std::cout << 0 << std::endl;
		}
	} else {
		int pipe_height_per_node = pipe_height/number_of_nodes;
		int nodes_with_additional_pipe = pipe_height - number_of_nodes*pipe_height_per_node;
		int number_of_active_nodes = pipe_height_per_node ? number_of_nodes : nodes_with_additional_pipe;

		long long *min_hole_diameters = new long long [number_of_active_nodes];

		int start_index;
		int end_index;

		if (my_node < nodes_with_additional_pipe) {
			start_index = (pipe_height_per_node + 1) * my_node;
			end_index = start_index + pipe_height_per_node + 1;
		} else {
			start_index = pipe_height_per_node * my_node + nodes_with_additional_pipe;
			end_index = start_index + pipe_height_per_node;
		}

		if (start_index > pipe_height) {
			return 0;
		}
		if (end_index > pipe_height) {
			end_index = pipe_height;
		}

		int max_index = end_index-start_index;

		long long min_hole_diameter = HoleDiameter(start_index + 1);

		for (int index = 1; index < max_index; index++) {
			long long hole_diameter = HoleDiameter(start_index + index + 1);
			if (hole_diameter < min_hole_diameter) {
				min_hole_diameter = hole_diameter;
			}
		}

		if (my_node == 0) {
			if (number_of_active_nodes > 1) {
				int target = 1;
				PutLL(target, min_hole_diameter);
				Send(target);
			}
		} else {
			int source = my_node - 1;
			Receive(source);
			long long min_hole_diameter_previous_pipe = GetLL(source);
			if (min_hole_diameter_previous_pipe < min_hole_diameter) {
				min_hole_diameter = min_hole_diameter_previous_pipe;
			}
			if (my_node < number_of_active_nodes - 1) {
				int target = my_node + 1;
				PutLL(target, min_hole_diameter);
				Send(target);
			}
		}

		min_hole_diameters[my_node] = min_hole_diameter;

		for (int index = 1; index < number_of_active_nodes; index++) {
			if (index != my_node) {
				PutLL(index, min_hole_diameter);
				Send(index);
			}
		}

		for (int index = 0; index < number_of_active_nodes; index++) {
			if (index != my_node) {
				int source = Receive(-1);
				long long source_min_hole_diameter = GetLL(source);
				min_hole_diameters[source] = source_min_hole_diameter;
			}
		}

		if (0 != my_node) {
			PutLL(0, min_hole_diameter);
			Send(0);
		}

		int discs_per_node = number_of_discs/number_of_nodes;
		int nodes_with_additional_disc = number_of_discs - number_of_nodes*discs_per_node;
		int nodes_with_discs = discs_per_node ? number_of_nodes : nodes_with_additional_disc;

		int disc_start_index;
		int disc_end_index;

		if (my_node < nodes_with_additional_disc) {
			disc_start_index = (discs_per_node + 1) * my_node;
			disc_end_index = disc_start_index + discs_per_node + 1;
		} else {
			disc_start_index = discs_per_node * my_node + nodes_with_additional_disc;
			disc_end_index = disc_start_index + discs_per_node;
		}

		if (disc_start_index > number_of_discs) {
			delete [] min_hole_diameters;
			return 0;
		}
		if (disc_end_index > number_of_discs) {
			disc_end_index = number_of_discs;
		}

		long long *normalized_disc_diameter = new long long[disc_end_index - disc_start_index];

		for (int index = disc_start_index + 1; index <= disc_end_index; index++) {
			int table_index = index - disc_start_index - 1;
			if (table_index == 0) {
				normalized_disc_diameter[table_index] = DiscDiameter(index);
			} else {
				if (normalized_disc_diameter[table_index - 1] > DiscDiameter(index)) {
					normalized_disc_diameter[table_index] = normalized_disc_diameter[table_index - 1];
				} else {
					normalized_disc_diameter[table_index] = DiscDiameter(index);
				}
			}
		}

		long long last_diameter = normalized_disc_diameter[disc_end_index - disc_start_index - 1];
		int pipe_index = 0;
		int last_pipe_index = pipe_height_per_node;
		if (nodes_with_additional_pipe > 0) {
			last_pipe_index++;
		}

		while (pipe_index < number_of_active_nodes
				&& min_hole_diameters[pipe_index] >= last_diameter
				&& HoleDiameter(last_pipe_index) >= last_diameter) {
			pipe_index++;
			last_pipe_index += pipe_height_per_node;
			if (pipe_index < nodes_with_additional_pipe) {
				last_pipe_index++;
			}
		}
		if (pipe_index == number_of_active_nodes) {
			pipe_index--;
		}

		int min_period_index = 0;
		int max_period_index = 0;
		if (pipe_index != 0 || last_diameter <= HoleDiameter(1)) {
			if (pipe_index < nodes_with_additional_pipe) {
				start_index = (pipe_height_per_node + 1) * pipe_index;
				end_index = start_index + pipe_height_per_node + 1;
			} else {
				start_index = pipe_height_per_node * pipe_index + nodes_with_additional_pipe;
				end_index = start_index + pipe_height_per_node;
			}

			if (start_index > pipe_height) {
				delete [] normalized_disc_diameter;
				delete [] min_hole_diameters;
				return 0;
			}
			if (end_index > pipe_height) {
				end_index = pipe_height;
			}

			int min_period_index = start_index;
			while (min_period_index < end_index && HoleDiameter(min_period_index + 1) >=  last_diameter) {
				min_period_index++;
			}
			max_period_index = min_period_index;

			for (int index = disc_end_index - 2; index >= disc_start_index; index--) {
				if(max_period_index < pipe_height
						&& HoleDiameter(max_period_index + 1) <= normalized_disc_diameter[index]) {
					max_period_index++;
				} else {
					min_period_index--;
				}
			}

			if (my_node != 0) {
				int source = 0;
				Receive(source);
				PutInt(source, min_period_index);
				PutInt(source, max_period_index);
				Send(source);
			} else {
				for (int index = 1; index < nodes_with_discs; index++) {
					Send(index);
					Receive(index);
					int target_min_period_index = GetInt(index);
					int target_max_period_index = GetInt(index);

					if (min_period_index > target_max_period_index) {
						min_period_index = target_min_period_index;
					} else {
						min_period_index -= target_max_period_index - target_min_period_index + 1;
					}
				}
				if (min_period_index <= 0) {
					std::cout << 0 <<std::endl;
				} else {
					std::cout << min_period_index <<std::endl;
				}
			}
		}

		delete [] normalized_disc_diameter;
		delete [] min_hole_diameters;
	}

	return 0;
}