1. “Introduction to Programming With Java”
Lecture – 5
UMESH PATIL

2. Contents for Today’s Lecture
Quick recap of the syllabus covered so far.
Solutions to previous assignments.
Some programing practice.
Introduction to Arrays.

3. Recap Structure of Java Program:
class class-name { public static void main(String args[]) {
statements;
} }
Printing messages to the screen:
System.out.println(“Hello World”); System.out.print(“Hello World”);

4. Recap…
Data Types: Numbers – int (whole no.s), double (no.s with decimal point) eg. int i = 23; double d = Character – char eg. char c = ‘a’; String – String eg. String s = “Hi”; Boolean – boolean eg. boolean b = false;
Variable declaration: data-type variable-name eg. int i = 23;

5. Recap…
Expression: An expression is a combination of literals (like 100), operators (like +), variables and parentheses used to calculate a value. eg / (2 – 9)
Operators: Arithmetic – eg. ‘-’, ‘+’, ‘/’, ‘++’ etc. Relational – eg. ‘<’, ‘>=’, ‘!=’ etc. Conditional – eg. ‘&&’ (AND), ‘||’ (OR)
Control constructs like‘if’ and ‘if else’:

6. Assignment
Write a program that averages the synsets created for three months April, May and June. Declare and initialize variable to the synset entered for each month. Compute the average and write out the results, something like this:
Synsets Entered for April: 12
Synsets Entered for May : 14
Synsets Entered for June: 8
Average Synset Entered:

7. Solution
class synset { public static void main(String args[]) { int april = 12; int may = 14; int june = 8; double avg; avg = ( april + may + june ) / 3.0;
System.out.println("Synsets Entered for April " + april); System.out.println("Synsets Entered for May " + may); System.out.println("Synsets Entered for June " + june); System.out.println("Average Synset Entered " + avg); } }

8. Assignment int a_number=1; (range is 1 to 5 both including)
Print the value in a_number in word with and without using equality (= =) operator. For example it should print “Four” if a_number contains 4.

9. Solution
class assign1 { public static void main(String args[]) { int a_number; a_number = 5;
if(a_number == 1) System.out.println("One");
if(a_number == 2) System.out.println("Two");
if(a_number == 3) System.out.println("Three");
if(a_number == 4) System.out.println("Four");
if(a_number == 5) System.out.println("Five"); } }

10. Arrays
Definition:
An array is a group/collection of variables of the same type that are referred to by a common name and an index
Examples:
Collection of numbers
Collection of names
Collection of suffixes

11. Examples 10 23 863 8 229 Sholay Shaan Shakti ment tion ness ves
Array of numbers:
Array of names:
Array of suffixes: 10 23
863 8
229
Sholay
Shaan
Shakti
ment
tion
ness
ves

12. Analogy Array is like a pen box with fixed no. of slots of same size.

13. End
Thank you…