NSMutableSet *intersection = [NSMutableSet setWithArray:newsmall];
//this shows an array of newsmall as expected
NSLog(@"intersection %@", intersection);
[intersection intersectSet:[NSSet setWithArray:newnewbig]];
//this shows nothing
NSLog(@"intersection %@", intersection);
//this shows an array of newnewbig as expected
NSLog(@"newnewbig %@", newnewbig);
NSArray *arrayfour = [intersection allObjects];
//this shows nothing
NSLog(@"arrayfour %@", arrayfour);
newsmall和newnewbig有一些匹配的字符串,所以我期望arrayfour顯示幾個字符串。NSSet的NSArray在NSLog中沒有任何顯示
我做錯了什麼?