├── README.md └── java programs ├── 1.java ├── 10.java ├── 11.java ├── 12.java ├── 13.java ├── 14.java ├── 15.java ├── 16.java ├── 2.java ├── 3.java ├── 4.java ├── 5.java ├── 6.java ├── 7.java ├── 8.java ├── 9.java ├── demo1.class ├── demo10.class ├── demo11.class ├── demo12.class ├── demo13.class ├── demo14.class ├── demo15.class ├── demo16.class ├── demo2.class ├── demo3.class ├── demo4.class ├── demo5.class ├── demo6.class ├── demo7.class ├── demo8.class └── demo9.class /README.md: -------------------------------------------------------------------------------- 1 | # java-basics 2 | -------------------------------------------------------------------------------- /java programs/1.java: -------------------------------------------------------------------------------- 1 | import java.util.Scanner; 2 | class demo1 3 | { 4 | static int sum=0; 5 | public static void main(String[] a) 6 | { 7 | Scanner scan =new Scanner(System.in); 8 | System.out.println("enter the range"); 9 | int num=scan.nextInt(); 10 | System.out.println("n natural number :- "); 11 | while(sum 0.0) 17 | { 18 | double r1 = (-b + Math.pow(d, 0.5)) / (2.0 * a); 19 | double r2 = (-b - Math.pow(d, 0.5)) / (2.0 * a); 20 | System.out.println("The roots are " + r1 + " and " + r2); 21 | } 22 | else if (d == 0.0) 23 | { 24 | double r1 = -b / (2.0 * a); 25 | System.out.println("The root is " + r1); 26 | } 27 | else 28 | { 29 | System.out.println("Roots are not real."); 30 | } 31 | } 32 | } -------------------------------------------------------------------------------- /java programs/15.java: -------------------------------------------------------------------------------- 1 | import java.util.Scanner; 2 | class demo15 3 | { 4 | public static void main(String[] a) 5 | { 6 | int sum=0; 7 | Scanner scan=new Scanner(System.in); 8 | int num=0; 9 | System.out.println("enter the range"); 10 | num=scan.nextInt(); 11 | while(num>0) 12 | { 13 | sum+=(num+Math.pow(num,2)); 14 | num--; 15 | } 16 | System.out.println("sum of square n natural numbers :- "+sum); 17 | 18 | } 19 | } -------------------------------------------------------------------------------- /java programs/16.java: -------------------------------------------------------------------------------- 1 | import java.util.Scanner; 2 | class demo16 3 | { 4 | 5 | static int nCr(int n, int r) 6 | { 7 | return fact(n) / (fact(r) * fact(n - r)); 8 | } 9 | static int fact(int n) 10 | { 11 | int res = 1; 12 | for (int i = 2; i <= n; i++) 13 | res = res * i; 14 | return res; 15 | } 16 | public static void main(String[] args) 17 | { 18 | Scanner scan=new Scanner(System.in); 19 | System.out.println("enter n and r values" ); 20 | int n=scan.nextInt(); 21 | int r=scan.nextInt(); 22 | System.out.println("The entered value of n is :"+ n); 23 | System.out.println("The entered value of r is :"+ r); 24 | if(n>=r) 25 | 26 | System.out.println("Value of "+ n+"C"+r+"= "+nCr(n, r)); 27 | else 28 | System.out.println("n value should be greater than or equals to r value"); 29 | 30 | } 31 | } 32 | -------------------------------------------------------------------------------- /java programs/2.java: -------------------------------------------------------------------------------- 1 | import java.util.Scanner; 2 | class demo2 3 | { 4 | static int sum=0; 5 | public static void main(String[] a) 6 | { 7 | Scanner scan =new Scanner(System.in); 8 | System.out.println("enter the range"); 9 | int num=scan.nextInt(); 10 | while(num>0) 11 | { 12 | sum+=num; 13 | num--; 14 | 15 | } 16 | System.out.println("SUM OF NATURAL NUMBERS :- "+sum); 17 | } 18 | 19 | } -------------------------------------------------------------------------------- /java programs/3.java: -------------------------------------------------------------------------------- 1 | import java.util.Scanner; 2 | class demo3 3 | { 4 | public static void main(String[] a) 5 | { 6 | String rev=""; 7 | Scanner scan=new Scanner(System.in); 8 | System.out.println("ENTER STRING"); 9 | String str=scan.nextLine(); 10 | StringBuilder temp=new StringBuilder(); 11 | for(int i=str.length()-1;i>-1;i--) 12 | { 13 | rev+=str.charAt(i); 14 | } 15 | if(str.equals(rev)) 16 | { 17 | System.out.println("IT IS A PALIDROM"); 18 | } 19 | else 20 | { 21 | System.out.println("IT IS NOT PALIDROM"); 22 | } 23 | 24 | } 25 | } -------------------------------------------------------------------------------- /java programs/4.java: -------------------------------------------------------------------------------- 1 | import java.util.Scanner; 2 | class demo4 3 | { 4 | public static void main(String[] a) 5 | { 6 | int rev=0; 7 | int temp; 8 | Scanner scan=new Scanner(System.in); 9 | System.out.println("enter the number"); 10 | int num =scan.nextInt(); 11 | int rel=num; 12 | while(rel!=0) 13 | { 14 | temp=rel%10; 15 | rev=rev+(temp*temp*temp); 16 | rel/=10; 17 | 18 | } 19 | if(rev==num) 20 | System.out.println("THE ARMSTRONG NUMBER IS:-"+rev); 21 | else 22 | System.out.println(rev+" THIS NOT ARMSTRONG NUMBER"); 23 | } 24 | } -------------------------------------------------------------------------------- /java programs/5.java: -------------------------------------------------------------------------------- 1 | import java.util.Scanner; 2 | class demo5 3 | { 4 | static int sum=0; 5 | public static void main(String[] a) 6 | { 7 | Scanner scan =new Scanner(System.in); 8 | System.out.println("enter the number"); 9 | float num=scan.nextFloat(); 10 | int i=0; 11 | while(i<=num/2) 12 | { 13 | 14 | 15 | if(num%i==0) 16 | { 17 | sum+=i; 18 | } 19 | i++; 20 | 21 | 22 | } 23 | 24 | if(num==sum) 25 | System.out.println("the perfect number is:- "+sum); 26 | else 27 | System.out.println("this is not perfect number"); 28 | 29 | } 30 | 31 | } -------------------------------------------------------------------------------- /java programs/6.java: -------------------------------------------------------------------------------- 1 | import java.sql.Blob; 2 | import java.util.Scanner; 3 | class demo6 4 | { 5 | public static void main(String[] ar) 6 | { 7 | Scanner scan=new Scanner(System.in); 8 | System.out.println("enter a number a:-"); 9 | int a=scan.nextInt(); 10 | System.out.println("enter a number b:-"); 11 | int b=scan.nextInt(); 12 | a=a^b; 13 | b=a^b; 14 | a=a^b; 15 | System.out.println("after swap two number a:-"+a); 16 | System.out.println("after swap two number b:-"+b); 17 | 18 | } 19 | 20 | } -------------------------------------------------------------------------------- /java programs/7.java: -------------------------------------------------------------------------------- 1 | import java.util.Scanner; 2 | 3 | 4 | class demo7 5 | { 6 | 7 | public static void main(String[] ar) 8 | { 9 | Scanner scan=new Scanner(System.in); 10 | System.out.println("ENTER NUMBER"); 11 | int num=scan.nextInt(); 12 | int fac=1; 13 | int i=1; 14 | 15 | while(i<=num) 16 | { 17 | fac=fac*i; 18 | i++; 19 | } 20 | System.out.println("factorail of given number:-"+fac); 21 | } 22 | } -------------------------------------------------------------------------------- /java programs/8.java: -------------------------------------------------------------------------------- 1 | import java.io.IOException; 2 | 3 | class demo8 4 | { 5 | public static void main(String[] ar)throws IOException 6 | { 7 | System.out.println("enter the character"); 8 | int num=System.in.read() ; 9 | System.out.printf("the ascii value of %c is %d",num,num); 10 | 11 | } 12 | } -------------------------------------------------------------------------------- /java programs/9.java: -------------------------------------------------------------------------------- 1 | import java.util.Scanner; 2 | class demo9 3 | { 4 | public static void main(String[] ar) 5 | { 6 | Scanner scan =new Scanner(System.in); 7 | System.out.println("enter the range"); 8 | int num= scan.nextInt(); 9 | int i,j; 10 | System.out.println("the prime numbers are:-"); 11 | for(i=2;i