@implementation SomeGenerater - (NSArray *)generateAThousandRandomStrings { NSMutableArray *strings = [[NSMutableArray alloc] initWithCapacity:1000]; for (int count = 0; count < 1000; count++) { int length = arc4random_uniform(10) + 4; unichar buf[length]; for (int idx = 0; idx < length; idx++) { buf[idx] = (unichar)('a' + arc4random_uniform(26)); } [strings addObject:[NSString stringWithCharacters:buf length:length]]; } return strings; } @end