Introduction to programming in java Lecture 22 Arrays – Part 2 and Assignment No. 3

Initializer Lists Declare Array – Syntax: type[] arrayName = new type[length] – Example: int[] studentID=new int[10]; Initializer List – You can declare, construct, and initialize the array all in one statement: – Example: int[] studentID={123,234,345,456,567,678,789,890,901}

Fill in the blanks so that the values in valA are copied into the corresponding cells of valB. class ArrayExp { public static void main(String[] args) { int[] valA = {12,23,45,56}; int valB = new int[4]; valB[0] = valA[0]; valB[1] = valA[1]; valB[2] = valA[2]; valB[3] = valA[3]; }}

Complete the assignment statement so that it computes the sum of all the numbers in the array. class Exercise1 { public static void main ( String[] args ) { int[] val = {0, 1, 2, 3}; sum = _________________________________ System.out.println( "Sum of all numbers = " + sum ); } val[0] + val[1] + val[2] + val[3] ;

The length of an Array What is the length of the following array? – int[] egArray = { 2, 4, 6, 8, 10, 1, 3, 5, 7, 9 }; We can use length instance variable. Examples System.out.println(“Length of egArray is “ + egArray.length); for ( int index= 0 ; index < egArray.length; index++ )

Practice Question # 1 Set up an array to hold the following values, and in this order: – 3, 1, 5, 7, 4, 12, -3, 8, -2. Write a program which identifies the largest number in the array.

Solution Practice more by yourself: find smallest number

Practice Question # 2 Set up a string array that contains name of the FCIT departments: – IT, CS, IS Write a program which takes department name from the user then program check whether the user provided department belongs to FCIT college or not.

Homework Assignment # 3 (Total marks: 5) Submission deadline: 19 th Nov 2013 NOTES: 1.Only HAND WRITTEN assignments are acceptable on A4 size white paper. 2.If any student copy assignment from other then -5 marks will be deducted from the overall grade. 3.Late submission is not allowed.

Question 1 Ask the user to enter in a number. Print out that many *’ s on the screen without spaces or newlines. Example: Please enter a number: 7 *******

Question 2 Write a program which prompts user to enter any sentence. Program will then print the whole sentence in reverse order. Example: Enter sentence: I like java programming..gnimmargorp avaj ekil I

Question 3 Ask the user to enter in a number. Write a program to find out if a number is prime or not? Example Enter number is a prime number.

Question 4 Examine the following program: Complete the program with four assignment statements so that each cell of sum contains the sum of the corresponding cells in valA and valB. I.e., add cell zero of valA to cell zero of valB and put the result in cell zero of sum, and so on.

Question 5 Define an integer array that contains the following values: int[] data = {3, 2, 5, 7, 9, 12, 97, 24, 54}; Write a program that computes – the sum of all the elements of the array, – the sum of the even elements, and – the sum of the odd elements.