what does mean to Design a recursive function to search a character in given string in c

Designing a recursive function to search for a character in a given string in C means creating a function that takes a character and a string as input and returns true if the character is present in the string and false otherwise, using recursion in the C programming language.

Here's an example 01 implementation in C:

#include<stdio.h>
char *strchr_recfun(const char *,char );
int main()
{
    char s[10],ch;
    printf("Enter the string:");
    scanf("%[^\n]",s);
    printf("Enter the character for searching:");
    scanf(" %c",&ch);
   if(strchr_recfun(s,ch))
   printf("Character is there in this string:\n");
   else
   printf("Charcater is not There in this string:\n");
   

}
char *strchr_recfun(const char *s,char ch)
{
    if(*s)
    {
        if(*s==ch)
        return s;
        else
        return strchr_recfun(s+1,ch);
    }
    else
    return 0;
}

Output:

Enter the string: Balmiki

Enter the character for searching: B

Character is there in this string

 

Enter the string: Balmiki

Enter the character for searching:b

Character is not There in this string:

 

Here's an example 02 implementation in C:

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

int search_character(char c, char *str);

int main() {
    char str[100], c;
    printf("Enter a string: ");
    fgets(str, 100, stdin);
    printf("Enter a character to search: ");
    scanf("%c", &c);
    if (search_character(c, str)) {
        printf("Character found\n");
    } else {
        printf("Character not found\n");
    }
    return 0;
}

int search_character(char c, char *str) {
    if (*str == '\0') {
        return 0;
    } else if (*str == c) {
        return 1;
    } else {
        return search_character(c, str + 1);
    }
}

In this implementation, we define a function search_character that takes a character c and a character pointer str as input. If the first character of str is the null character ('\0'), which signifies the end of the string, we return 0 to indicate that the character is not found. Otherwise, if the first character of str is the character we are searching for (c), we return 1 to indicate that the character is found. Otherwise, we recursively call the search_character function on the rest of the string (str + 1). This checks the rest of the string for the character recursively.

Note that in this implementation, we return an integer instead of a boolean value. 0 is used to represent false and 1 is used to represent true. This is because C does not have a boolean type. If you are using a C++ compiler, you can use the bool type and return true or false instead of 1 or 0.