NSArray* arr = @[@"1",@"2",@"3"];
arr = [arr sortedArrayUsingComparator:^NSComparisonResult(NSString *str1, NSString *str2) {
int seed = arc4random_uniform(2);
if (seed) {
return [str1 compare:str2];
} else {
return [str2 compare:str1];
}
原文：https://www.cnblogs.com/shenlaiyaoshi/p/9436662.html