JAVA CLASSES

classes01.java

```java
/* 

Program 01
Write a program to take your name as input from user through keyboard and display a greeting 

*/

import java.util.Scanner;

public class Greeting {
    public static void main(String[] args) {
    Scanner s = new Scanner(System.in);
    System.out.print("Enter your name: ");
    String name = s.nextLine();
    System.out.println("Hello " + name + " !!!");
 
    }
}

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/* 

Program 02
Write a program that inputs, calculates and displays the average of three numbers 

*/

import java.util.Scanner;

public class Clac {
    public static void main(String args[]) {
        float n1, n2, n3, sum, avg;
        
        Scanner kb = new Scanner(System.in);
        System.out.println("Enter 3 numbers :");
        
        n1 = kb.nextFloat();
        n2 = kb.nextFloat();
        n3 = kb.nextFloat();
        
        sum = n1 + n2 + n3;
        avg = sum / 3;
        
        System.out.println("You entered : " + n1 + " , " + n2 + " , " + n3 );
        System.out.println("Their average is = " + avg);
    }
}

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/*

Program 03
Write a program to read a time in minutes and split it into days, hours and minutes.

*/
    
import java.util.Scanner;

public class Time {
    public static void main(String args[]) {
        final int hoursInDay = 24;
        final int minsInHour = 60;
        
        int totMins; 
        int totHrs;
        int days = 0, hours = 0, mins = 0;
        
        Scanner Keyboard = new Scanner(System.in);
        System.out.print("Enter total minutes: ");
        
        totMins = Keyboard.nextInt(); 
        totHrs = totMins / minsInHour;  
        mins = totMins % minsInHour;  
        days = totHrs / hoursInDay; 
        hours = totHrs % hoursInDay; 
        
        System.out.println(totMins + " minutes is " + days + " days, " + hours + " hours and " + mins + " minutes");
        
    }
}

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/*
Program 04
Write a program that inputs principal amount, rate of interest and time and calculates compound interest.

*/

import java.util.Scanner;

public class CalcInterest {
    public static void main(String args[]) {
        double principal, time, rate, amount, cinterest;
        
        Scanner kb = new Scanner(System.in);
        System.out.print("Enter the principal amount: ");
        principal = kb.nextDouble();
        
        System.out.print("Enter time (in years): ");
        time = kb.nextDouble();
        
        System.out.print("Enter interest rate (%): ");
        rate = kb.nextDouble();
        
        amount = principal * Math.pow((100 + rate)/100, time);
        cinterest = amount - principal;
        
        System.out.println("Principal Amount = " + principal);
        System.out.println("Time invested for " + time + " years");
        System.out.println("At " + rate + "% invested");
        System.out.println("Compound Interest generated = " + cinterest);
        
        System.out.println("Final Amount is: " + amount);
        
        
        
        
    }
}

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/*
Program 05
Write a program to calculate the distance between 2 points (x1, y1) and (x2, y2)

Hint: Use Distance Formula of Coordinate Geometry
*/
    
import java.util.Scanner;

public class Distance {
    public static void main(String args[]) {
        int x1, x2, y1, y2;
        
        double dist;
        
        Scanner kb = new Scanner(System.in);
        System.out.print("Enter the x1 value: ");
        x1 = kb.nextInt();
        
        System.out.print("Enter the x2 value: ");
        x2 = kb.nextInt();
        
        System.out.print("Enter the y1 value: ");
        y1 = kb.nextInt();
        
        System.out.print("Enter the y2 value: ");
        y2 = kb.nextInt();
        
        dist = Math.sqrt( Math.pow((x2 - x1), 2) + Math.pow((y2-y1), 2));
        
        System.out.println("Distance between the given coordinates is: " + dist);
        
    }
}
    
```
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/*
Program 06
Write a program to print sum of three given numbers 1221, 2332, 3443.

*/
    
    
    
/*
Program 07
Write a program to find the perimeter of a triangle with sides measuring 10cm, 14cm, and 15cm

*/
    
 /*
 Program 08
 Write a program to find the side of the square whose perimeter is 20m
 
 */