STL in OOP: Containers, Iterators, and Algorithms, Slides of Object Oriented Programming

Download STL in OOP: Containers, Iterators, and Algorithms and more Slides Object Oriented Programming in PDF only on Docsity!

Object-Oriented Programming

(OOP)

Lecture No. 41

Standard Template Library

• C++ programmers commonly use many

data structures and algorithms

• So C++ standard committee added the

STL to C++ standard library

• STL is designed to operate efficiently

across many different applications

STL Promotes Reuse

• Software reuse saves development time

and cost

• Once tested component can be reused

several times

STL Containers

• Container is an object that contains a

collection of data elements

• STL provides three kinds of containers
  • Sequence Containers
  • Associative Containers
  • Container Adapters

…Sequence Containers

• vector
  • Rapid insertions and deletions at back end
  • Random access to elements
• deque
  • Rapid insertions and deletions at front or back
  • Random access to elements
• list
  • Doubly linked list
  • Rapid insertions and deletions anywhere

Example – STL Vector

#include

int main() {

std::vector< int > iv; int x, y; char ch; do { cout<<"Enter the first integer:"; cin >> x; cout<<"Enter the second integer:"; cin >> y;

Sample Output

Enter the first integer: 1

Enter the second integer: 2

Current capacity of iv = 2

Current size of iv = 2

Do you want to continue? y

…Sample Output

Enter the first integer: 3

Enter the second integer: 4

Current capacity of iv = 4

Current size of iv = 4

Do you want to continue? y

Example – STL Deque

#include

int main() {

std::deque< int > dq; dq.push_front( 3 ); dq.push_back( 5 );

dq.pop_front(); dq.pop_back() return 0;

}

Example – STL List

#include

int main() {

std::list< float > _list; _list.push_back( 7.8 ); _list.push_back( 8.9 ); std::list< float >::iterator it = _list.begin(); _list.insert( ++it, 5.3 ); return 0;

}

…Associative Containers

• set
  • No duplicates
• multiset
  • Duplicates allowed
• map
  • No duplicate keys
• multimap
  • Duplicate keys allowed

Example – STL Set

#include

int main() {

std::set< char > cs; cout << “Size before insertions: “ << cs.size() << endl; cs.insert( ‘a’ ); cs.insert( ‘b' ); cs.insert( ‘b' ); cout << “Size after insertions: ” << cs.size(); return 0;

} Docsity.com

Example – STL Multi-Set

#include

int main() {

std::multiset< char > cms; cout << "Size before insertions: " << cms.size() << endl; cms.insert( 'a' ); cms.insert( 'b' ); cms.insert( 'b' ); cout << "Size after insertions: " << cms.size(); return 0;

} Docsity.com

Output

Size before insertions: 0

Size after insertions: 3