Strings in C Part – 2

Program 1

// Program for string lower to upper and upper to lower
#include<stdio.h>
#include<conio.h>
#include<string.h>
int main()
{
    char str[50];
    int len,i;
    system("cls");
    printf("Enter a string in lower case: ");
    gets(str); 
      // using inbuild
    //puts(strupr(str));

    // without using inbuild
        i=0;
        while(str[i]!='\0')
        {
            printf("%c",str[i]-32);
            i++;
        }

    return 0;
}

Program 2

// Program for string lower to upper and upper to lower
#include<stdio.h>
#include<conio.h>
#include<string.h>
int main()
{
    char str[50];
    int len,i;
    system("cls");
    printf("Enter a string in Upper case: ");
    gets(str); 
      // using inbuild
    //puts(strlwr(str));

    //without using inbuild
        i=0;
        while(str[i]!='\0')
        {
            if(str[i]==' ')
            printf("%c",str[i]);
            else
            printf("%c",str[i]+32);
            i++;
        }

    return 0;
}

Program 3

// Program for reverse string 
#include<stdio.h>
#include<conio.h>
#include<string.h>
int main()
{
    char str[50];
    int len,i;
    system("cls");
    printf("Enter a string :");
    gets(str); 
    
    //puts(strrev(str));

    // Without inbuild function
       for(i=strlen(str)-1;i>=0;i--)
       {
          printf("%c",str[i]);
       }
    return 0;
}

Program 4

// Program for Palindrom string
#include<stdio.h>
#include<conio.h>
#include<string.h>
int main()
{
    char str[50];
    int i,j,f;
    system("cls");
    printf("Enter a string :");
    gets(str); 
    i=0;
    j=strlen(str)-1;
    f=0;
    while(i<=j)
    {
        if(str[i]!=str[j])
        {
              f=1;
              break;
        }
             i++;
             j--;
    }
    if(f==0)
      printf("String is palindrom");
     else
     printf("String is not palindrom");
    
    return 0;
}