Program to check whether string is palindrome or not without using library function

Program to check whether string is palindrome or not without using library function

#include<stdio.h>

 void main()

{

            char s[20];

            int i=0, len, flag = 0;

            printf("\nEnter s1: ");

            gets(s);

            /*To find the length of the string*/

            while(s[i]!='\0')

            {

                        i++;

            }

            len = i;

            for(i=0; i<len/2; i++)

            {

                        if(s[i] != s[len-i-1])

                        {

                                    flag = 1;

                                    break;

                        }

            }

            if(flag == 0)

                        printf("\nString is palindrome.");

            else

                        printf("\nString is not palindrome.");

}

Output:

Enter s1: abcba

Strings is palindrome.

Program to check whether string is palindrome or not

Program to check whether string is palindrome or not

#include<stdio.h>
#include<string.h>

void main()
{
          char s1[20], s2[20];
          printf("\nEnter s1: ");
          gets(s1);

          /*Copy s1 contents to s2*/
          strcpy(s2, s1);

          /*Reverse s2*/
          strrev(s2);

          /*Compare s1 and s2*/
          if(strcmp(s1, s2) == 0)
                  printf("\nString is palindrome.");
          else
                 printf("\nString is not a palindrome");

}

Output:
case 1:
Enter s1: abcde
String is not a palindrome


case 2:
Enter s1: abcba
String is palindrome.

Program to compare two strings without using library function strcmp

Program to compare two strings without using library function strcmp

#include<stdio.h>

#include<string.h>

void main()

{

       int len1, len2, flag = 0, i;

      char s1[20], s2[20];

      printf("\nEnter s1: ");

      gets(s1);

      printf("\nEnter s2: ");

      gets(s2);

      len1 = strlen(s1);

      len2 = strlen(s2);

      if(len1 != len2)

      {

             flag = 1;

      }

     else

     {

            for(i=0;i<len1;i++)

           { 

                 if(s1[i] != s2[i])

                {

                       flag = 1;

                       break;

                 }

          }

    }

    if(flag == 0)

        printf("\nStrings are same.");

    else

        printf("\nStrings are different.");

}

Output:

Case 1:

Enter s1: abcde

Enter s2: abcdef

Strings are different.

Case 2:

Enter s1: abcde

Enter s2: abfgh

Strings are different.

Case 3:

Enter s1: abcde

Enter s2: abcde

Strings are same.

Program for arithmetic calculator using switch

Program to demo arithmetic calculator using switch

#include<stdio.h>
void main()
{
             int a, b;
             float res;
             char op;
             printf("\nEnter a op b :");
             scanf("%d %c %d", &a, &op, &b);
             switch(op)
            {
                         case  '+' :       res = a+b;
                                              break;
                         case  '-' :        res = a-b;
                                              break;
                         case  '*' :        res = a * b;
                                              break;
                          case  '/' :        if(!b)
                                                      printf("\n Divide by zero error");
                                               else
                                                      res = (float)a/b;
                                               break;
                          case  '%' :      res = a % b;
                                               break;
                          default:        printf("\nGive valid operator+");
                                              break;
            }
            printf("\n Result = %f", res);
}

Output:

Enter a op b : 1   /    2
Result = 0.500000

Write a program to check whether character is vowel or consonant

Program to check whether character is vowel or consonant

#include<stdio.h>

void main()

{

             char ch;

             printf("\nEnter the character:");

             scanf("%c", &ch);

             switch(ch)

            {

                      case 'a':

                      case 'e':

                      case 'i':

                      case 'o':

                      case 'u':    printf("\nGiven character is vowel");

                                       break;

                      default:     printf("\nGiven character is consonant");

                                       break;

           }

}

Output:

Enter the character: o

Given character is vowel

Enter the character: t

Given character is consonant

Program to print pattern using for loop

Program to print pattern using for loop

1

2 2

3 3 3

4 4 4 4

5 5 5 5 5

#include<stdio.h>

void main()

{

                 int i,j,row;

                printf("Enter the number of rows you want:");

                scanf("%d",&row);

                 for(i=1;i<=row;i++)

                {

                                for(j=1;j<=i;j++)

                                {

                                                printf("%d ",i);

                                }

                                printf("\n");

                }  

}

Output:

Enter the number of rows you want: 5

1

2 2

3 3 3

4 4 4 4

5 5 5 5 5

Program to print pattern using for loop

Program to print pattern using for loop

  1

  2   3

  4   5   6

  7   8   9  10

 11  12  13  14  15

#include<stdio.h>

main()

{

                int row,i,j,c=1;

                printf("Enter the number of rows you want: \n");

                scanf("%d",&row);

                for(i=1;i<=row;i++)

                {

                                for(j=1;j<=i;j++)

                                {

                                                printf("%3d ",c);

                                                 c++;

                                }

                                printf("\n");

                }           

}

Enter the number of rows you want:  5 

  1

  2   3

  4   5   6

  7   8   9  10

 11  12  13  14  15

Program to print pattern using for loop

Program to print pattern using for loop

* * * * *

* * * *

* * *

* *

*

#include<stdio.h>

void main()

{

                int row,i,j;

                printf("Enter the number of rows you want: \n");

                scanf("%d",&row);

                for(i=row;i>=1;i--)

                {

                                for(j=1;j<=i;j++)

                                 {

                                                printf("* ");

                                }

                                printf("\n");

                }

}

Output:

Enter the number of rows you want: 5

* * * * *

* * * *

* * *

* *

*

Program to print pattern using for loop

Program to print pattern using for loop

*
* *
* * *
* * * *

#include<stdio.h>

void main()

{

                int row,i,j;

                printf("Enter the number of rows you want: ");

                scanf("%d",&row);

               

                for(i=1;i<=row;i++)

                {

                                for(j=1;j<=i;j++)

                                {

                                                printf("* ");

                                }

                                printf("\n");

                }             

}

Enter the number of rows you want: 5

*

* *

* * *

* * * *

* * * * *