In Predicate Programming Guide, please refer https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/Predicates/Articles/pUsing.html.
Here,
NSPredicate *sPredicate = [NSPredicate predicateWithFormat:@"SELF contains[c] 'e'"];
[array filterUsingPredicate:sPredicate];
// array now contains { @"Nick", @"Ben", @"Melissa" }.
The output is wrong here.
It must be // array now contains { @"Ben", @"Melissa" }