Serial and binary search program in c using class
Although we can use an array to store a group of elements of the same type either primitives or objects. The array, however, does not support so-called dynamic allocation - it has a fixed length which cannot be changed once allocated.
Furthermore, array is a simple linear structure. Many applications may require more complex data structure such as linked list, stack, hash table, sets, or trees.
In Java, dynamically allocated data structures such as ArrayListLinkedListVectorStackHashSetHashMapHashtable are supported in a unified architecture called the Collection Frameworkwhich mandates the common behaviors of all the classes. A collectionas its name implied, is simply an object that holds a collection or a group, a container of objects. Each item in a collection is called an element. A frameworkby definition, is a set of interfaces that force you to adopt serial and binary search program in c using class design practices.
A well-designed framework can improve your productivity and provide ease of maintenance. The collection framework provides a unified interface to store, retrieve and manipulate the elements of a collection, regardless of the underlying and actual implementation. This allows the programmers serial and binary search program in c using class program at the interfaces, instead of the actual implementation.
Prior to JDK 1. The collection framework is retrofitted to support generics and takes full advantages of these new features. The classes and interfaces for the Collection Framework are kept in package java. Let's begin with an example of a Collection - an ArrayList. The ArrayList is a linear data structure, similar to the array, but resizable.
Recall that a Collection is an object that holds a collection or a group, or a container of elements. Below is an example of using an ArrayList to hold a collection of String objects. You may need to compile this program with option -Xlint: You will receive some warning messages.
We will resolve these warnings later. This example illustrates the unified architecture of the Collection Framework, defined in the interfaces Collection and its sub-interfaces ListSetQueueIterableand Iterator. You can program on these interfaces instead of the actual implementations. However, when you retrieve an element from a collection in the form of Object it is the programmer's responsibility to downcast the Object back to its original class, before further manipulation can take place.
You are certainly familiar with passing arguments into methods. You place the arguments inside the round bracket and pass them to the method. Based on this type information, compiler is able serial and binary search program in c using class check the type of argument for the add methods, and issues an compilation error for Line 20, when you attempt to add an Integer object.
The compiler can also automatically insert the proper downcast operator in Line 16 and detect the wrong type in Line 21 in the get methods in retrieving the elements of the collection. Take note that in the earlier pre-JDK 1. The loop variable str will take on each element of the lst in the loop-body.
You may need to include serial and binary search program in c using class -Xlint: The compiler issues these warning messages to warn you about the unsafe operations i. You could go ahead and execute the serial and binary search program in c using class with warnings.
A collection contains only objects. It cannot holds primitives such as int and double. Although arrays can be used to hold primitives, they are not resizable. To put a primitive into a collection such as ArrayListyou have to wrap the primitive into an object using the corresponding wrapper class as shown below:.
The codes for collection can be quite messy and more importantly, not type-safe. With generics, autoboxing and for-each loop, JDK 1. The hierarchy of the interfaces and the commonly-used implementation classes in the Collection Framework is as shown below:.
This Iterator object can then be used to transverse through all the elements of the associated collection. All implementations of the collection e. As seen in the introductory example, you can use a while-loop to iterate through the elements with the Iterator as follows:. Besides using the Iterator as described in the previous sectionJDK 1. The loop variable item will take on each of the element of the collection, in each iteration of the loop-body.
See the introductory section on example. The enhanced for-loop provides a convenience way to transverse through a collection of elements. On the other hand, as the loop variable receives a "cloned" serial and binary search program in c using class of the object reference, the enhanced for-loop can be used to modify "mutable" elements such as StringBuilder via the "cloned" object references, but it cannot modify "immutable" objects such as String and primitive wrapper classes as new references are created.
It defines the common behaviors expected of all classes, such as how to add or remove an element, via the following abstract methods:.
Primitive values are to be wrapped into objects via the respective wrapper classes such as Integer and Double. Read " Auto-Boxing and Auto-Unboxing " section for example. In practice, we typically program on one of the sub-interfaces of the Collection interface: The details of these sub-interfaces and implementations will be covered later in the implementation section. No duplicate key is allowed. The details will serial and binary search program in c using class covered later.
In practice, it is more common to program on the one of the sub-interfaces of Collection: ListSetor Queueinstead of the super-interface Collection. These sub-interfaces further refine the behaviors of the Collection. Elements in a list can be retrieved and inserted at a specific index position based on an int index. It can contain duplicate elements. It can contain null elements. You can search a list, iterate through its elements, and perform operations on a selected range of values in the list.
Since List has a positional index. Operation such as addremoveset can be applied to an element at a specified index position. The abstract superclass AbstractList provides implementation to many of the abstract methods declared in the ListCollectorand Iterable interfaces. However, some methods such as get int index remains abstract. These methods will be implemented by the concrete subclasses such as ArrayList and Vector. Many useful methods are already implemented in AbstractList but overridden for efficiency in ArrayList e.
Vector is a synchronized implementation of the List interface. It also contains additional legacy methods e. There is no reason to use these legacy methods - other than to maintain backward compatibility. ArrayList is not synchronized. The integrity of ArrayList instances is not guaranteed under multithreading. Instead, it is the programmer's responsibility to ensure synchronization. On the other hand, Vector is synchronized internally. Read " Synchronized Collection " if you are dealing with multi-threads.
Java Performance Tuning Tip: Hence, if synchronization is not an issue, you should use ArrayList instead of Vector for better performance. Stack extends Vectorwhich is a synchronized resizable array, with five additional methods:. The super-interface Collection defines a method called toArray to create an array based on this list. The returned array is free for modification. The utility class java.
Arrays provides a static method Arrays. However, change to the list write-thru the array and vice versa. Take note that the name of the method is asList and not toList. It define one abstract method:. This ordering is referred to as the class's natural orderingand the class's compareTo method is referred to as its natural comparison method.
It is strongly recommended that compareTo be consistent with equals and hashCode inherited from java. All the eight primitive wrapper classes ByteShortIntegerLongFloatDoubleCharacter and Boolean implement Comparable interface, with the compareTo uses the numeric order. Collections provide many static method for the various algorithms such as sorting and searching Refer to " Algorithms " for details. In this example, we use the Arrays. The default Comparable of String compares two Strings based on their underlying Unicodes, i.
Besides the Comparable or the natural orderingyou can pass a Comparator object into the sorting methods Collections.
The Comparator will override the Comparableif available. In this example, instead of using the default Comparablewe define our customized Comparator for String s and Integer s. Modify the Comparator to sort in A, a ,B, b, C, c It may contain a single serial and binary search program in c using class element. The insertion, deletion and inspection methods returns false if the operation fails, instead of throws an exception.
Let's write a Book class, and create a Set of Book objects.
You compare strings to answer one of two questions: The C examples in this article run in the Try. NET inline code runner and playground.
Select the Run button to run an example in an interactive window. Once you execute the code, you can modify it and run the modified code by selecting Run again. The modified code either runs in the interactive window or, if compilation fails, the interactive window displays all C compiler error messages. When you compare strings, you define an order among them. Comparisons are used to sort a sequence of strings. Once the sequence is in a known order, it is easier to search, both for software and for humans.
Other comparisons may check if strings are the same. These sameness checks are similar to equality, but some differences, such as case differences, may be ignored. The most common operations, String. Equality use an ordinal comparison, a case-sensitive comparison, and use the current culture. Serial and binary search program in c using class results are shown in the following example. Ordinal comparisons do not take linguistic rules into account when comparing strings.
They will compare the strings character by character. Case-sensitive comparisons use capitalization in their comparisons. The most important point about these default comparison methods is that because they use the current culture, the results depend on the locale and language settings of the machine where they run. These serial and binary search program in c using class are unsuitable for comparisons where order should be consistent across machines or locations. Equals method enables you to specify a StringComparison value of StringComparison.
Serial and binary search program in c using class to specify a case-insensitive comparison. There is also a static Compare method that includes a boolean argument to specify case-insensitive comparisons. These are shown in the following code:. Strings can also be ordered using linguistic rules for the current culture.
This is sometimes referred to as "word sort order. For example, the hyphen "-" may have a very small weight assigned to serial and binary search program in c using class so that "co-op" and "coop" appear next to each other in sort order. In addition, some Unicode characters may be equivalent to a sequence of alphanumeric characterss. The following example uses the phrase "They dance in the street. Linguistically in Windows"ss" is equal to the German Essetz: This sample demonstrates the operating system dependent nature of linguistic comparisons.
The host for the interactive window is a Linux host. The linguistic and ordinal comparisons produce the same results. If you ran this same sample on a Windows host, you would see the following output:. On Windows, the sort order of "cop", "coop", and "co-op" change when you change from a linguistic comparison to an ordinal comparison. The two German sentences also compare differently using the different comparison types. This sample stores CultureInfo for the current culture.
The original culture can be set and retrieved on the current thread object. The comparisons are performed using the CurrentCulture value to ensure a culture-specific comparison. The culture used affects linguistic comparisons. The following example shows the results of comparing the two German sentences using the "en-US" culture and the "de-DE" culture:. Culture-sensitive comparisons are typically used to compare and sort strings input by users with other strings input by users.
The characters and sorting conventions of these strings might vary depending on the locale of the user's computer. Even strings that contain identical characters might sort differently depending on the culture of the current thread. In addition, try this sample code locally on a Windows machine, and you will the following results:.
Linguistic comparisions are dependent on the current culture, and are OS dependent. You must take that into account when serial and binary search program in c using class work with string comparisons. The following examples show how to sort and search for strings in an array using a linguistic comparison dependent on the current culture. You use the static Array methods that take a System. Once the array is sorted, you can search for entries using a serial and binary search program in c using class search.
A binary search starts in the middle of the collection to determine which half of the collection would contain the sought string. Each subsequent comparison subdivides the remaining part of the collection in half. The array is sorted using StringComparer. The local function ShowWhere displays information about where the string was found. If the string was not found, the returned value indicates where it would be if it were found. The following code uses the Serial and binary search program in c using class. This method needs a delegate that compares and orders two strings.
CompareTo method provides that comparison function. Run the sample and observe the order. This sort operation uses an ordinal case sensitive sort. You would use the static String. Compare methods to specify different comparison rules.
Once sorted, the list of strings can be searched using a binary search. The following sample shows how to search the sorted listed using the same comparison function. The local function ShowWhere shows where the sought text is or would be:. Always make sure to use the same type of comparison for sorting and searching. Using different comparison types for sorting and searching produces unexpected results.
Collection classes such as System. StringComparer parameter when the type of the elements or keys is string. In general, you should use these constructors whenever possible, and specify either StringComparer. None of the samples have used ReferenceEquals. This method determines if two strings are the same object. This can lead to inconsistent results in string comparisons. The following example demonstrates the string interning feature of C.
When a program declares two or more identical string variables, the compiler stores them all in the same location. By calling the ReferenceEquals method, you can see that the two strings actually refer to the same object in memory.
Copy method to avoid interning. After the copy has been made, the two strings have different storage locations, even though they have the same value. Run the following sample to show that strings a and b are interned meaning they share the same storage.
The strings a and c are not. When you test for equality of strings, you should use the methods that explicitly specify what kind of comparison you intend to perform. Your code is much more maintainable and readable. Use the overloads of the methods of the System. Array classes that take a StringComparison enumeration parameter. You specify which type of comparison to perform. CompareTo instance methods always perform an ordinal case-sensitive comparison.
They are primarily suited for ordering strings alphabetically. The feedback system for this content will be changing soon. Old comments will not be carried over. If content within a comment thread is important to you, please save a copy. For more information on the upcoming change, we invite you to read our blog post. You can choose an ordinal or linguistic comparison. You can choose serial and binary search program in c using class case matters.
You can choose culture specific comparisons. Linguistic comparisions are culture and platform dependent. Note The C examples in this article run in the Try. Note When you test for equality of strings, you should use the methods that explicitly specify what kind of comparison you intend to perform. Note The feedback system for this content will be changing soon.