NSArray数组通过kvc得到最大值

NSArray *allValues = @[ [NSNumber numberWithInt:20],                        [NSNumber numberWithInt:36],                        [NSNumber numberWithInt:84],                        [NSNumber numberWithInt:11],                        [NSNumber numberWithInt:28]];int max = [[allValues valueForKeyPath:@"@max.intValue"] intValue];int min = [[allValues valueForKeyPath:@"@min.intValue"] intValue];

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