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d288ee65 1/*
2 * Copyright (c) 2009-2012, Pieter Noordhuis <pcnoordhuis at gmail dot com>
3 * Copyright (c) 2009-2012, Salvatore Sanfilippo <antirez at gmail dot com>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * * Redistributions of source code must retain the above copyright notice,
10 * this list of conditions and the following disclaimer.
11 * * Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * * Neither the name of Redis nor the names of its contributors may be used
15 * to endorse or promote products derived from this software without
16 * specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30
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PN
31#include <stdio.h>
32#include <stdlib.h>
33#include <string.h>
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34#include "intset.h"
35#include "zmalloc.h"
7a3e3720 36#include "endianconv.h"
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37
38/* Note that these encodings are ordered, so:
39 * INTSET_ENC_INT16 < INTSET_ENC_INT32 < INTSET_ENC_INT64. */
40#define INTSET_ENC_INT16 (sizeof(int16_t))
41#define INTSET_ENC_INT32 (sizeof(int32_t))
42#define INTSET_ENC_INT64 (sizeof(int64_t))
43
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PN
44/* Return the required encoding for the provided value. */
45static uint8_t _intsetValueEncoding(int64_t v) {
46 if (v < INT32_MIN || v > INT32_MAX)
47 return INTSET_ENC_INT64;
48 else if (v < INT16_MIN || v > INT16_MAX)
49 return INTSET_ENC_INT32;
dc75b1ed 50 else
51 return INTSET_ENC_INT16;
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PN
52}
53
54/* Return the value at pos, given an encoding. */
55static int64_t _intsetGetEncoded(intset *is, int pos, uint8_t enc) {
dc75b1ed 56 int64_t v64;
57 int32_t v32;
58 int16_t v16;
59
60 if (enc == INTSET_ENC_INT64) {
61 memcpy(&v64,((int64_t*)is->contents)+pos,sizeof(v64));
62 memrev64ifbe(&v64);
63 return v64;
64 } else if (enc == INTSET_ENC_INT32) {
65 memcpy(&v32,((int32_t*)is->contents)+pos,sizeof(v32));
66 memrev32ifbe(&v32);
67 return v32;
68 } else {
69 memcpy(&v16,((int16_t*)is->contents)+pos,sizeof(v16));
70 memrev16ifbe(&v16);
71 return v16;
72 }
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PN
73}
74
75/* Return the value at pos, using the configured encoding. */
76static int64_t _intsetGet(intset *is, int pos) {
6136a16b 77 return _intsetGetEncoded(is,pos,intrev32ifbe(is->encoding));
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PN
78}
79
80/* Set the value at pos, using the configured encoding. */
81static void _intsetSet(intset *is, int pos, int64_t value) {
6136a16b 82 uint32_t encoding = intrev32ifbe(is->encoding);
83
84 if (encoding == INTSET_ENC_INT64) {
76864d56 85 ((int64_t*)is->contents)[pos] = value;
dc75b1ed 86 memrev64ifbe(((int64_t*)is->contents)+pos);
6136a16b 87 } else if (encoding == INTSET_ENC_INT32) {
76864d56 88 ((int32_t*)is->contents)[pos] = value;
dc75b1ed 89 memrev32ifbe(((int32_t*)is->contents)+pos);
90 } else {
76864d56 91 ((int16_t*)is->contents)[pos] = value;
dc75b1ed 92 memrev16ifbe(((int16_t*)is->contents)+pos);
93 }
76864d56 94}
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95
96/* Create an empty intset. */
97intset *intsetNew(void) {
98 intset *is = zmalloc(sizeof(intset));
6136a16b 99 is->encoding = intrev32ifbe(INTSET_ENC_INT16);
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100 is->length = 0;
101 return is;
102}
103
104/* Resize the intset */
105static intset *intsetResize(intset *is, uint32_t len) {
6136a16b 106 uint32_t size = len*intrev32ifbe(is->encoding);
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107 is = zrealloc(is,sizeof(intset)+size);
108 return is;
109}
110
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111/* Search for the position of "value". Return 1 when the value was found and
112 * sets "pos" to the position of the value within the intset. Return 0 when
113 * the value is not present in the intset and sets "pos" to the position
114 * where "value" can be inserted. */
115static uint8_t intsetSearch(intset *is, int64_t value, uint32_t *pos) {
6136a16b 116 int min = 0, max = intrev32ifbe(is->length)-1, mid = -1;
d0b58d53 117 int64_t cur = -1;
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118
119 /* The value can never be found when the set is empty */
6136a16b 120 if (intrev32ifbe(is->length) == 0) {
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121 if (pos) *pos = 0;
122 return 0;
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123 } else {
124 /* Check for the case where we know we cannot find the value,
125 * but do know the insert position. */
6136a16b 126 if (value > _intsetGet(is,intrev32ifbe(is->length)-1)) {
127 if (pos) *pos = intrev32ifbe(is->length);
3ab98cef 128 return 0;
76864d56 129 } else if (value < _intsetGet(is,0)) {
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130 if (pos) *pos = 0;
131 return 0;
132 }
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133 }
134
135 while(max >= min) {
136 mid = (min+max)/2;
76864d56 137 cur = _intsetGet(is,mid);
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138 if (value > cur) {
139 min = mid+1;
140 } else if (value < cur) {
141 max = mid-1;
142 } else {
143 break;
144 }
145 }
146
147 if (value == cur) {
148 if (pos) *pos = mid;
149 return 1;
150 } else {
151 if (pos) *pos = min;
152 return 0;
153 }
154}
155
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PN
156/* Upgrades the intset to a larger encoding and inserts the given integer. */
157static intset *intsetUpgradeAndAdd(intset *is, int64_t value) {
6136a16b 158 uint8_t curenc = intrev32ifbe(is->encoding);
f9d5c4e3 159 uint8_t newenc = _intsetValueEncoding(value);
6136a16b 160 int length = intrev32ifbe(is->length);
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PN
161 int prepend = value < 0 ? 1 : 0;
162
163 /* First set new encoding and resize */
6136a16b 164 is->encoding = intrev32ifbe(newenc);
165 is = intsetResize(is,intrev32ifbe(is->length)+1);
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166
167 /* Upgrade back-to-front so we don't overwrite values.
168 * Note that the "prepend" variable is used to make sure we have an empty
169 * space at either the beginning or the end of the intset. */
170 while(length--)
171 _intsetSet(is,length+prepend,_intsetGetEncoded(is,length,curenc));
172
173 /* Set the value at the beginning or the end. */
174 if (prepend)
175 _intsetSet(is,0,value);
176 else
6136a16b 177 _intsetSet(is,intrev32ifbe(is->length),value);
178 is->length = intrev32ifbe(intrev32ifbe(is->length)+1);
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PN
179 return is;
180}
181
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182static void intsetMoveTail(intset *is, uint32_t from, uint32_t to) {
183 void *src, *dst;
6136a16b 184 uint32_t bytes = intrev32ifbe(is->length)-from;
185 uint32_t encoding = intrev32ifbe(is->encoding);
186
187 if (encoding == INTSET_ENC_INT64) {
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188 src = (int64_t*)is->contents+from;
189 dst = (int64_t*)is->contents+to;
190 bytes *= sizeof(int64_t);
6136a16b 191 } else if (encoding == INTSET_ENC_INT32) {
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192 src = (int32_t*)is->contents+from;
193 dst = (int32_t*)is->contents+to;
194 bytes *= sizeof(int32_t);
195 } else {
196 src = (int16_t*)is->contents+from;
197 dst = (int16_t*)is->contents+to;
198 bytes *= sizeof(int16_t);
199 }
200 memmove(dst,src,bytes);
201}
202
203/* Insert an integer in the intset */
204intset *intsetAdd(intset *is, int64_t value, uint8_t *success) {
76864d56 205 uint8_t valenc = _intsetValueEncoding(value);
740eee1c 206 uint32_t pos;
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207 if (success) *success = 1;
208
209 /* Upgrade encoding if necessary. If we need to upgrade, we know that
210 * this value should be either appended (if > 0) or prepended (if < 0),
211 * because it lies outside the range of existing values. */
6136a16b 212 if (valenc > intrev32ifbe(is->encoding)) {
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213 /* This always succeeds, so we don't need to curry *success. */
214 return intsetUpgradeAndAdd(is,value);
144b0094 215 } else {
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216 /* Abort if the value is already present in the set.
217 * This call will populate "pos" with the right position to insert
218 * the value when it cannot be found. */
219 if (intsetSearch(is,value,&pos)) {
220 if (success) *success = 0;
221 return is;
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PN
222 }
223
6136a16b 224 is = intsetResize(is,intrev32ifbe(is->length)+1);
225 if (pos < intrev32ifbe(is->length)) intsetMoveTail(is,pos,pos+1);
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226 }
227
76864d56 228 _intsetSet(is,pos,value);
6136a16b 229 is->length = intrev32ifbe(intrev32ifbe(is->length)+1);
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230 return is;
231}
232
233/* Delete integer from intset */
a5be65f7 234intset *intsetRemove(intset *is, int64_t value, int *success) {
76864d56 235 uint8_t valenc = _intsetValueEncoding(value);
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236 uint32_t pos;
237 if (success) *success = 0;
238
6136a16b 239 if (valenc <= intrev32ifbe(is->encoding) && intsetSearch(is,value,&pos)) {
240 uint32_t len = intrev32ifbe(is->length);
241
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242 /* We know we can delete */
243 if (success) *success = 1;
244
245 /* Overwrite value with tail and update length */
6136a16b 246 if (pos < (len-1)) intsetMoveTail(is,pos+1,pos);
247 is = intsetResize(is,len-1);
248 is->length = intrev32ifbe(len-1);
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PN
249 }
250 return is;
251}
252
253/* Determine whether a value belongs to this set */
254uint8_t intsetFind(intset *is, int64_t value) {
76864d56 255 uint8_t valenc = _intsetValueEncoding(value);
6136a16b 256 return valenc <= intrev32ifbe(is->encoding) && intsetSearch(is,value,NULL);
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257}
258
259/* Return random member */
260int64_t intsetRandom(intset *is) {
6136a16b 261 return _intsetGet(is,rand()%intrev32ifbe(is->length));
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PN
262}
263
d0b58d53
PN
264/* Sets the value to the value at the given position. When this position is
265 * out of range the function returns 0, when in range it returns 1. */
266uint8_t intsetGet(intset *is, uint32_t pos, int64_t *value) {
6136a16b 267 if (pos < intrev32ifbe(is->length)) {
76864d56 268 *value = _intsetGet(is,pos);
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PN
269 return 1;
270 }
271 return 0;
272}
273
274/* Return intset length */
275uint32_t intsetLen(intset *is) {
6136a16b 276 return intrev32ifbe(is->length);
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PN
277}
278
d4fb9f41 279/* Return intset blob size in bytes. */
280size_t intsetBlobLen(intset *is) {
6136a16b 281 return sizeof(intset)+intrev32ifbe(is->length)*intrev32ifbe(is->encoding);
d4fb9f41 282}
283
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284#ifdef INTSET_TEST_MAIN
285#include <sys/time.h>
286
287void intsetRepr(intset *is) {
288 int i;
6136a16b 289 for (i = 0; i < intrev32ifbe(is->length); i++) {
76864d56 290 printf("%lld\n", (uint64_t)_intsetGet(is,i));
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291 }
292 printf("\n");
293}
294
295void error(char *err) {
296 printf("%s\n", err);
297 exit(1);
298}
299
300void ok(void) {
301 printf("OK\n");
302}
303
304long long usec(void) {
305 struct timeval tv;
306 gettimeofday(&tv,NULL);
307 return (((long long)tv.tv_sec)*1000000)+tv.tv_usec;
308}
309
310#define assert(_e) ((_e)?(void)0:(_assert(#_e,__FILE__,__LINE__),exit(1)))
311void _assert(char *estr, char *file, int line) {
312 printf("\n\n=== ASSERTION FAILED ===\n");
313 printf("==> %s:%d '%s' is not true\n",file,line,estr);
314}
315
316intset *createSet(int bits, int size) {
317 uint64_t mask = (1<<bits)-1;
318 uint64_t i, value;
319 intset *is = intsetNew();
320
321 for (i = 0; i < size; i++) {
322 if (bits > 32) {
323 value = (rand()*rand()) & mask;
324 } else {
325 value = rand() & mask;
326 }
327 is = intsetAdd(is,value,NULL);
328 }
329 return is;
330}
331
332void checkConsistency(intset *is) {
333 int i;
334
6136a16b 335 for (i = 0; i < (intrev32ifbe(is->length)-1); i++) {
336 uint32_t encoding = intrev32ifbe(is->encoding);
337
338 if (encoding == INTSET_ENC_INT16) {
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339 int16_t *i16 = (int16_t*)is->contents;
340 assert(i16[i] < i16[i+1]);
6136a16b 341 } else if (encoding == INTSET_ENC_INT32) {
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342 int32_t *i32 = (int32_t*)is->contents;
343 assert(i32[i] < i32[i+1]);
344 } else {
345 int64_t *i64 = (int64_t*)is->contents;
346 assert(i64[i] < i64[i+1]);
347 }
348 }
349}
350
351int main(int argc, char **argv) {
352 uint8_t success;
353 int i;
354 intset *is;
355 sranddev();
356
357 printf("Value encodings: "); {
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358 assert(_intsetValueEncoding(-32768) == INTSET_ENC_INT16);
359 assert(_intsetValueEncoding(+32767) == INTSET_ENC_INT16);
360 assert(_intsetValueEncoding(-32769) == INTSET_ENC_INT32);
361 assert(_intsetValueEncoding(+32768) == INTSET_ENC_INT32);
362 assert(_intsetValueEncoding(-2147483648) == INTSET_ENC_INT32);
363 assert(_intsetValueEncoding(+2147483647) == INTSET_ENC_INT32);
364 assert(_intsetValueEncoding(-2147483649) == INTSET_ENC_INT64);
365 assert(_intsetValueEncoding(+2147483648) == INTSET_ENC_INT64);
366 assert(_intsetValueEncoding(-9223372036854775808ull) == INTSET_ENC_INT64);
367 assert(_intsetValueEncoding(+9223372036854775807ull) == INTSET_ENC_INT64);
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368 ok();
369 }
370
371 printf("Basic adding: "); {
372 is = intsetNew();
373 is = intsetAdd(is,5,&success); assert(success);
374 is = intsetAdd(is,6,&success); assert(success);
375 is = intsetAdd(is,4,&success); assert(success);
376 is = intsetAdd(is,4,&success); assert(!success);
377 ok();
378 }
379
380 printf("Large number of random adds: "); {
381 int inserts = 0;
382 is = intsetNew();
383 for (i = 0; i < 1024; i++) {
384 is = intsetAdd(is,rand()%0x800,&success);
385 if (success) inserts++;
386 }
6136a16b 387 assert(intrev32ifbe(is->length) == inserts);
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PN
388 checkConsistency(is);
389 ok();
390 }
391
392 printf("Upgrade from int16 to int32: "); {
393 is = intsetNew();
394 is = intsetAdd(is,32,NULL);
6136a16b 395 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT16);
144b0094 396 is = intsetAdd(is,65535,NULL);
6136a16b 397 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT32);
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PN
398 assert(intsetFind(is,32));
399 assert(intsetFind(is,65535));
400 checkConsistency(is);
401
402 is = intsetNew();
403 is = intsetAdd(is,32,NULL);
6136a16b 404 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT16);
144b0094 405 is = intsetAdd(is,-65535,NULL);
6136a16b 406 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT32);
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PN
407 assert(intsetFind(is,32));
408 assert(intsetFind(is,-65535));
409 checkConsistency(is);
410 ok();
411 }
412
413 printf("Upgrade from int16 to int64: "); {
414 is = intsetNew();
415 is = intsetAdd(is,32,NULL);
6136a16b 416 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT16);
144b0094 417 is = intsetAdd(is,4294967295,NULL);
6136a16b 418 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT64);
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PN
419 assert(intsetFind(is,32));
420 assert(intsetFind(is,4294967295));
421 checkConsistency(is);
422
423 is = intsetNew();
424 is = intsetAdd(is,32,NULL);
6136a16b 425 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT16);
144b0094 426 is = intsetAdd(is,-4294967295,NULL);
6136a16b 427 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT64);
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PN
428 assert(intsetFind(is,32));
429 assert(intsetFind(is,-4294967295));
430 checkConsistency(is);
431 ok();
432 }
433
434 printf("Upgrade from int32 to int64: "); {
435 is = intsetNew();
436 is = intsetAdd(is,65535,NULL);
6136a16b 437 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT32);
144b0094 438 is = intsetAdd(is,4294967295,NULL);
6136a16b 439 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT64);
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PN
440 assert(intsetFind(is,65535));
441 assert(intsetFind(is,4294967295));
442 checkConsistency(is);
443
444 is = intsetNew();
445 is = intsetAdd(is,65535,NULL);
6136a16b 446 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT32);
144b0094 447 is = intsetAdd(is,-4294967295,NULL);
6136a16b 448 assert(intrev32ifbe(is->encoding) == INTSET_ENC_INT64);
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PN
449 assert(intsetFind(is,65535));
450 assert(intsetFind(is,-4294967295));
451 checkConsistency(is);
452 ok();
453 }
454
455 printf("Stress lookups: "); {
456 long num = 100000, size = 10000;
457 int i, bits = 20;
458 long long start;
459 is = createSet(bits,size);
460 checkConsistency(is);
461
462 start = usec();
463 for (i = 0; i < num; i++) intsetSearch(is,rand() % ((1<<bits)-1),NULL);
464 printf("%ld lookups, %ld element set, %lldusec\n",num,size,usec()-start);
465 }
466
467 printf("Stress add+delete: "); {
468 int i, v1, v2;
469 is = intsetNew();
470 for (i = 0; i < 0xffff; i++) {
471 v1 = rand() % 0xfff;
472 is = intsetAdd(is,v1,NULL);
473 assert(intsetFind(is,v1));
474
475 v2 = rand() % 0xfff;
e24d9376 476 is = intsetRemove(is,v2,NULL);
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PN
477 assert(!intsetFind(is,v2));
478 }
479 checkConsistency(is);
480 ok();
481 }
482}
483#endif