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
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
// (K?)MP and Rabin Karp based on http://www.geeksforgeeks.org/
#include <iostream>
#include <climits>
#include <cmath>

#include "poszukiwania.h"
#include "message.h"

//#define LOCAL

using namespace std;

typedef long long ll;

const ll SINGLE_TRES = 10ll * 1024 * 1024;
const ll MASTER = 0;

ll pattern_size;
ll text_size;
ll node_id;
int nodes_count;

typedef struct st {
	ll* _mem;
	ll _size;

	explicit st(ll size) :
			_mem(NULL), _size(size) {

		_mem = new ll[size];
	}

	ll& operator[](ll i) {
		return _mem[i];
	}
} string_ll;

inline ll SeqAtS(ll pos) {
	return SeqAt(pos + 1);
}

inline ll SignalAtS(ll pos) {
	return SignalAt(pos + 1);
}

void compute_shift_array(string_ll& pattern, int shift_array[]) {
	shift_array[0] = 0;

	int current_match = 0;
	int pattern_idx = 1;
	while (pattern_idx < pattern._size) {
		if (pattern._mem[pattern_idx] == pattern._mem[current_match]) {
			shift_array[pattern_idx++] = ++current_match;
		} else {
			if (current_match) {
				current_match = shift_array[current_match - 1];
			} else {
				shift_array[pattern_idx++] = 0;
			}
		}
	}
}

int search_pattern_kmp(string_ll& pattern, string_ll& text) {
	int res = 0;

	if (pattern._size < 1 || text._size < 1) {
		return 0;
	}

	int *shift_array = new int[pattern._size];
	compute_shift_array(pattern, shift_array);

	int pattern_idx = 0;
	int text_idx = 0;
	while (text_idx < text_size) {
		if (pattern._mem[pattern_idx] == text._mem[text_idx]) {
			pattern_idx++;
			text_idx++;
		}

		if (pattern_idx == pattern._size) {
			++res;
			pattern_idx = shift_array[pattern_idx - 1];
		} else if (text_idx < text._size && pattern._mem[pattern_idx] != text._mem[text_idx]) {
			if (pattern_idx != 0)
				pattern_idx = shift_array[pattern_idx - 1];
			else
				text_idx = text_idx + 1;
		}

		if (text._size - text_idx < pattern._size - pattern_idx) {
			break;
		}
	}

	delete[] shift_array;
	return res;
}

ll search_pattern_kmp_online(string_ll& pattern, ll text_start, ll text_end) {
	ll res = 0;

	if (pattern._size < 1 || text_end < 1 || text_end - text_start < 1) {
		return 0;
	}

	int *shift_array = new int[pattern._size];
	compute_shift_array(pattern, shift_array);

	int pattern_idx = 0;
	int text_idx = text_start;
	while (text_idx < text_end) {
		if (pattern._mem[pattern_idx] == SeqAtS(text_idx)) {
			pattern_idx++;
			text_idx++;
		}

		if (pattern_idx == pattern._size) {
			++res;
			pattern_idx = shift_array[pattern_idx - 1];
		} else if (text_idx < text_end && pattern._mem[pattern_idx] != SeqAtS(text_idx)) {
			if (pattern_idx != 0)
				pattern_idx = shift_array[pattern_idx - 1];
			else
				text_idx = text_idx + 1;
		}

		if (text_size - text_idx < pattern._size - pattern_idx) {
			break;
		}
	}

	delete[] shift_array;
	return res;
}

ll search_pattern_rk_online(ll text_start, ll text_end) {
//	cout << text_start << " " << text_end << endl;
		int d = (1 << 30) + 1;
//		ll q = 2147483647;
		ll q = 1023;
		ll res = 0;

    ll M = pattern_size;
    ll N = text_end - text_start;
    ll i, j;
    ll p = 0;  // hash value for pattern
    ll t = 0; // hash value for txt
    ll h = 1;

    // The value of h would be "pow(d, M-1)%q"
    for (i = 0; i < M-1; i++)
        h = (h*d)%q;
//    cout << h << " " << d << endl;

    // Calculate the hash value of pattern and first window of text
    for (i = 0; i < M; i++)
    {
        p = (d*p + SignalAtS(i))%q;
        t = (d*t + SeqAtS(text_start + i))%q;
//        t = (d*(t - SeqAtS(i)*h+q) + SeqAtS(i+M))%q;
    }
//    cout << "x" << p << " " << t << endl;

    // Slide the pattern over text one by one
    for (i = text_start; i <= text_start + N - M; i++)
    {

        // Check the hash values of current window of text and pattern
        // If the hash values match then only check for characters on by one
        if ( p == t )
        {
            /* Check for characters one by one */
            for (j = 0; j < M; j++)
            {
                if (SeqAtS(i+j) != SignalAtS(j))
                    break;
            }
            if (j == M)  // if p == t and pat[0...M-1] = txt[i, i+1, ...i+M-1]
            {
//                printf("Pattern found at index %d \n", i);
                ++res;
            }
        }

        // Calculate hash value for next window of text: Remove leading digit,
        // add trailing digit
        if ( i < N-M )
        {
//        	ll tmp = (d*(t - SeqAtS(i)*h+q) + SeqAtS(i+M))%q;
//            t = (d*(t - SeqAtS(i)*h) + SeqAtS(i+M))%q;
            t = (d*(t - (SeqAtS(i)*h)%q) + SeqAtS(i+M))%q;

//            if(t != tmp){
//            	cout << "# " << t << " " << tmp << endl;
//            }
//
//            t = tmp;
            // We might get negative value of t, converting it to positive
            if(t < 0)
              t = (t + q);
        }
    }

    return res;
}

//ll search_pattern_rk_online(ll text_start, ll text_end) {
//	ll res = 0;
//
//	ll d = (1ll << 30);
////	ll q = 2147483647;
//	ll q = 1023 * 1023;
//
//	ll text_size = text_end - text_start;
//	ll i, j;
//	ll p = 0;
//	ll t = 0;
//	ll h = 1;
//
//	for (i = 0; i < pattern_size - 1; i++) {
//		h = (h * d) % q;
//	}
//	h = 1;
//	cout << "# " << h << endl;
//
//	for (i = 0; i < pattern_size; i++) {
//		p = (d * p + SignalAtS(i)) % q;
//		t = (d * t + SeqAtS(text_start + i)) % q;
//	}
//
//	cout << p << endl;
//
//	for (i = 0; i <= text_size - pattern_size; i++) {
//
//		if (p == t) {
//			for (j = 0; j < pattern_size; j++) {
//				if (SeqAtS(text_start + i + j) != SignalAtS(j)) {
//					break;
//				}
//			}
//			if (j == pattern_size) {
//				cout << text_start + i << endl;
//				++res;
//			}
//		}
//
//		if ((text_start + i - 10000000) % 40000000 == 0) {
//			cout << p << " " << t << endl;
//		}
//
//		if (i < text_size - pattern_size) {
////			t = (d * (t - SeqAtS(text_start + i) * h) + SeqAtS(text_start + i + pattern_size)) % q;
//			t = (d * (t - (SeqAtS(text_start + i) * h) % q) + SeqAtS(text_start + i + pattern_size)) % q;
//
//			if (t < 0) {
//				t = (t + q);
//			}
//		}
//	}
//
//	return res;
//}

void single_kmp() {
	string_ll text(text_size);
	string_ll pattern(pattern_size);

	for (int i = 0; i < text_size; ++i) {
		text[i] = SeqAtS(i);
	}

	for (int i = 0; i < pattern_size; ++i) {
		pattern[i] = SignalAtS(i);
	}

	cout << search_pattern_kmp(pattern, text) << endl;
}

#ifndef LOCAL
void send_res(ll res) {
	PutLL(MASTER, res);
	Send(MASTER);
}

ll gather_res() {
	ll res = 0;

	for (int i = MASTER + 1; i < nodes_count; ++i) {
		Receive(i);
		res += GetLL(i);
	}

	return res;
}
#endif

ll kmp_in(ll my_start, ll my_end) {
	string_ll pattern(pattern_size);

	for (int i = 0; i < pattern_size; ++i) {
		pattern[i] = SignalAtS(i);
	}

	return search_pattern_kmp_online(pattern, my_start, my_end + pattern_size - 1);
}

ll rk_in(ll my_start, ll my_end) {
	return search_pattern_rk_online(my_start, my_end + pattern_size - 1);
}

void dist_shift(ll (*fn)(ll, ll)) {
#ifdef LOCAL
	for (int i = 0; i < nodes_count; ++i) {
		node_id = i;
#endif
		ll start_first = 0;
		ll start_lastn = text_size - pattern_size + 1;
		ll size = start_lastn - start_first;

		ll step = size / nodes_count;
		ll rest = size % nodes_count;

		ll my_start = start_first + min(node_id, rest) + node_id * step;
		ll my_end = start_first + min(node_id + 1, rest) + (node_id + 1) * step;

		ll res = fn(my_start, my_end);

#ifndef LOCAL
		if (node_id != MASTER) {
			send_res(res);
		} else {
			res += gather_res();
			cout << res << endl;
		}
#endif

#ifdef LOCAL
		cout << node_id << " " << res << endl;
	}
#endif

}

void dist_kmp() {
	dist_shift(kmp_in);
}

void dist_rk() {
	dist_shift(rk_in);
}

int main() {
	text_size = SeqLength();
	pattern_size = SignalLength();

#ifndef LOCAL
	node_id = MyNodeId();
	nodes_count = NumberOfNodes();
#else
	node_id = 0;
	nodes_count = 10;
#endif

	if (text_size <= SINGLE_TRES && pattern_size <= SINGLE_TRES) {
		if (node_id == 0) {
			single_kmp();
		}
		return 0;
	}

	if (pattern_size <= SINGLE_TRES) {
		dist_kmp();
		return 0;
	}

	dist_kmp();
//	dist_rk();

	return 0;
}