Question

Java

Q1: Create a class named Triangle, the class must contain:

• Private data fields base and height with setter and getter methods.
• A constructor that sets the values of base and height.
• A method named toString() that prints the values of base and height.
• A method named area() that calculates and prints the area of a triangle.

• Draw the UML diagram for the class.
• Implement the class.

Q2: Write a Java program that creates a two-dimensional array of type integer of size x by y (x and y must be entered by the user). The program must fill the array with random numbers from 1 to 100. The program must prompt the user to enter a search key between 1 and 100. Then, the program must check whether the search key is available in the array and print its location.

Here is a sample run:

Enter the number of rows: 5

Enter the number of columns: 5

Enter a search key between 1-100: 27

The key you entered is available at row 3, column 2.

Here is another sample run:

Enter the number of rows: 5

Enter the number of columns: 5

Enter a search key between 1-100: 33

The key you entered is not available in the array.

Answer 1

Q1:

import java.util.*;
public class Triangle {
private double base,height;
public void setBase(double b) {
   base = b;
}
public void setHeight(double h) {
   height = h;
}
public double getBase() {
   return(base);
}
public double getHeight() {
   return(height);
}
public Triangle(double b,double h) {
   base = b;
   height = h;
}
public void toMyString() {
   System.out.println("Base of the triangle: "+base+"\nHeight of the triangle: "+height);
}
public void area() {
   System.out.println("area of the triangle: "+0.5*base*height);
}
}
public class TriangleMain {
public static void main(String args[]) {
   Triangle t1 = new Triangle(7,8);
   t1.toMyString();
   t1.area();
}
}

Output

Q2:

import java.util.*;
public class Array {
   public static int[] searchArray(int[][] a,int x,int y,int n) {
       for(int i=0;i<x;i++) {
       for(int j=0;j<y;j++) {
           if(a[i][j] == n)
               return new int[] {i,j};               
       }        
   }
       return null;
   }
public static void main(String args[]) {
   int x,y,search;
   Scanner s = new Scanner(System.in);
   Random r = new Random();
   System.out.print("Enter the number of rows: ");
   x = s.nextInt();
   System.out.print("Enter the number of columns: ");
   y = s.nextInt();
   int [][]array = new int[x][y];
   for(int i=0;i<x;i++) {
       for(int j=0;j<y;j++) {
           array[i][j] = r.nextInt(100-1)+1;
       }
   }
   /* To print the array
   for(int i=0;i<x;i++) {
       for(int j=0;j<y;j++) {
           System.out.print(array[i][j]+" ");
       }
       System.out.println();
   }
   */
   System.out.print("Enter a search key between 1-100: ");
   search = s.nextInt();
   int[] values = new int[2];
   values = searchArray(array,x,y,search);
   if (values != null)
       System.out.println("The key you entered is available at row "+(values[0]+1)+",column "+(values[1]+1));
   else
       System.out.println("The key you entered is not available in the array");
}
}