Introduction of Loops and Array with syntax and Example

3. Object Oriented Programming
Presented by:
Naveed Hussain
Presented to:
Mr. Rana Mudassir
Topic:
Basics of Loops and Arrays
Class:
MCS 2nd Semester

4. Object Oriented Programming
Loops
Array

5. Loops

6. • In programming languages , loops
are used to execute a set of
instructions / function
s repeatedly when some conditions
become t rue.

7. Type s of Loops
For loop
While loop
Do While loop

8. For loop:
The Java for loop is used to
iterate a part of the program
several times. If the number of
iteration is fixed, it is
recommended to use for loop.

9. Types of“For Loop”
For each Loop
Simple For Loop
Labeled For Loop
For Loop

10. Simple For Loop:
The simple for loop is
same as C/C++. We can initialize
variable, check condition and
increment/decrement value.
Syntax:
for(initialization;condition;incr/dec
r)
{
//code to be executed
}

11. For each Loop:
The for-each loop is used to traverse
array or collection in java. It is easier to use than simple
for loop because we don't need to increment value and
use subscript notation.
It works on elements basis not index. It returns element
one by one in the defined variable.
Syntax:
for(Type var:array)
{
//code to be executed
}

12. Labeled For Loop:
We can have name of each for loop.
To do so, we use label before the for loop. It is useful if
we have nested for loop so that we can break/continue
specific for loop. “Normally, break and continue
keywords breaks/continues the inner most for loop only”.
Syntax:
labelname:
for(initialization;condition;incr/decr)
{
//code to be executed
}

13. While Loop:
The Java while loop is
used to iterate a part of the
program several times. If the
number of iteration is not fixed,it is
recommended to use while loop.
Syntax:
while(condition)
{
//code to be executed
i++/i--;
}

14. Do-While Loop:
If the number of iteration is not fixed
and you must have to execute the
loop at least once, it is recommended
to use do-while loop.The Java do-
while loop is executed at least once
because condition is checked after
loop body.
Syntax:
do
{
//code to be executed
}
while(condition);

16. Array:
 Array is an object the contains elements of similar
data type.
 Stores similar elements.
 Stores fixed set of elements in array.

17. Single Dimensional
Array
Click Multi-Dimensional
Array
Arrays

18. Single Dimensional Array:
One dimensional array is a list of same typed
variables. To create an array, first you must declare an
array variable of required type.

19. Syntax of Declare an Array:
 DataType[] arr;
 DataType []arr;
 DataType arr[];
Exapmle:
int a[]=new int[5];//declaration and instantiation
a[0]=10;//initialization
a[1]=20;
a[2]=70;
a[3]=40;
a[4]=50;

20. Multi-Dimensional Array:
The arrays you have been
using so far have only held one column of data. But you
can set up an array to hold more than one column.
These are called multi-dimensional arrays.

21. Syntax to Declare:
 dataType[][] arrayRefVar;
 dataType [][]arrayRefVar;
 dataType arrayRefVar[][];
 dataType []arrayRefVar[];
Example:
int[][] arr=new int[2][2];//2 row and 2 column
arr[0][0]=1;
arr[0][1]=2;
arr[1][2]=3;
arr[1][3]=4;