- (IBAction)generateSerial:(id)sender { int serialPart1 = (random() % 1400) + 143; serialPart1 *= 7; int serialPart2 = (random() % 752) + 79; serialPart2 *= 13; int serialPart3 = (random() % 452) + 49; serialPart3 *= 22; int serialPart4 = (random() % 362) + 39; serialPart4 *= 27; //First part = 7 //Second Part = 13 //Third Part = 22 //Fourth Part = 27 NSString *final = [NSString stringWithFormat: @"CAPP-%d-%d-%d-%d", serialPart1, serialPart2, serialPart3, serialPart4]; [serialEdit setStringValue:final]; }