Decimal to binary conversion

#include <stdio.h>
 
int main()
{
  int n, c, k;
 
  printf("Enter an integer in decimal number system\n");
  scanf("%d", &n);
 
  printf("%d in binary number system is:\n", n);
 
  for (c = 31; c >= 0; c--)
  {
    k = n >> c;
 
    if (k & 1)
      printf("1");
    else
      printf("0");
  }
 
  printf("\n");
 
  return 0;
}

Palindrome number program c

Palindrome number algorithm

1. Get the number from user.
2. Reverse it.
3. Compare it with the number entered by the user.
4. If both are same then print palindrome number
5. Else print not a palindrome number.

 -----------------------------------------------------------

#include<stdio.h>
 
main()
{
   int n, reverse = 0, temp;
 
   printf("Enter a number to check if it is a palindrome or not\n");
   scanf("%d",&n);
 
   temp = n;
 
   while( temp != 0 )
   {
      reverse = reverse * 10;
      reverse = reverse + temp%10;
      temp = temp/10;
   }
 
   if ( n == reverse )
      printf("%d is a palindrome number.\n", n);
   else
      printf("%d is not a palindrome number.\n", n);
 
   return 0;
}

c program to print pattern stars

#include<stdio.h>
 
main()
{
   int row, c, n, temp;
 
   printf("Enter the number of rows in pyramid of stars you wish to see ");
   scanf("%d",&n);
 
   temp = n;
 
   for ( row = 1 ; row <= n ; row++ )
   {
      for ( c = 1 ; c < temp ; c++ )
         printf(" ");
 
      temp--;
 
      for ( c = 1 ; c <= 2*row - 1 ; c++ )
         printf("*");
 
      printf("\n");
   }
 
   return 0;

Code for Armstrong number in c

#include<stdio.h>

int main(){

    int num,r,sum=0,temp;

    printf("Enter a number: ");

    scanf("%d",&num);

    temp=num;

    while(num!=0)

    {

         r=num%10;

         num=num/10;

         sum=sum+(r*r*r);

    }

    if(sum==temp)

         printf("%d is an Armstrong number",temp);

    else

         printf("%d is not an Armstrong number",temp);

    return 0;

}

---------------------------------------------------------------------------------------

Sample output:

Enter a number: 153

153 is an Armstrong number

Pascal triangle in c

   1
  1 1
 1 2 1
1 3 3 1 

---------------------------------------------------------------------

#include<stdio.h>
 
long factorial(int);
 
main()
{
   int i, n, c;
 
   printf("Enter the number of rows you wish to see in pascal

   triangle\n");
   scanf("%d",&n);
 
   for ( i = 0 ; i < n ; i++ )
   {
      for ( c = 0 ; c <= ( n - i - 2 ) ; c++ )
         printf(" ");
 
      for( c = 0 ; c <= i ; c++ )
         printf("%ld ",factorial(i)/(factorial(c)*factorial(i-c)));
 
      printf("\n");
   }
 
   return 0;
}
 
long factorial(int n)
{
   int c;
   long result = 1;
 
   for( c = 1 ; c <= n ; c++ )
         result = result*c;
 
   return ( result );
}

Hash table demo (JAVA)

import  java.util.*;
import java.io.*;
class demo_hashtable
{   public static  void main(String args[]) throws IOException
    {   BufferedReader br = new BufferedReader( new InputStreamReader(System.in));
         int opt;
         String name;
         double per , maxp;
         Enumeration n;
         Hashtable HT = new Hashtable();
         do
         {  System.out.println("\n1. Add student ");
             System.out.println("2. Display students ");
             System.out.println("3. Search student ");
            System.out.println("4. Find Highest percentage ");
            System.out.println("5. Exit ");
           System.out.print("Enter your option :  ");
           opt = Integer.parseInt(br.readLine());
          switch(opt)
         {   case  1: System.out.print("Enter Name : ");
                           name = br.readLine();
                          System.out.print("Enter percentage : ");
                         per = Double.parseDouble(br.readLine());
                        HT.put(name , per);  
                         break;
           case  2:  System.out.println(HT);
                         break;
            case  3:  System.out.print("Enter Name : ");
                          name = br.readLine();
                          if(HT.containsKey(name))
                                System.out.println("Percentage : " + HT.get(name));
                          else
                              System.out.println(name + " not present in hashtable");
                          break;
            case  4:  n = HT.keys();
                          per = maxp =0.0;
                          name = "";
                       while(n.hasMoreElements())
                      { String str =(String)n.nextElement();
                            per = (Double) HT.get(str);
                            if( per > maxp)
                           {  maxp = per;
                                name = str;
                           }                        
                       }
                       System.out.println("Student : " + name +" Highest Percentage : "+maxp);
                        break;
          case  5 : System.exit(0);
                     
        default : System.out.println("Wrong Option");
       }//switch
    }while(opt != 5);
    }
}