36 lines
871 B
Objective-C
36 lines
871 B
Objective-C
#import <Foundation/Foundation.h>
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typedef NSArray *(^SOfN)(id);
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SOfN s_of_n_creator(int n) {
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NSMutableArray *sample = [NSMutableArray arrayWithCapacity:n];
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__block int i = 0;
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return [[^(id item) {
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i++;
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if (i <= n) {
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[sample addObject:item];
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} else if (rand() % i < n) {
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[sample replaceObjectAtIndex:rand() % n withObject:item];
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}
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return sample;
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} copy] autorelease];
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}
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int main(int argc, const char *argv[]) {
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NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
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NSCountedSet *bin = [[NSCountedSet alloc] init];
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for (int trial = 0; trial < 100000; trial++) {
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SOfN s_of_n = s_of_n_creator(3);
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NSArray *sample;
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for (int i = 0; i < 10; i++)
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sample = s_of_n([NSNumber numberWithInt:i]);
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[bin addObjectsFromArray:sample];
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}
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NSLog(@"%@", bin);
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[bin release];
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[pool release];
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return 0;
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}
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