Read a string as an input using scanf

You have to make four changes:

1. Change

   char * str[25];
   

   to

   char str[25];
   

   as you want an array of 25 chars, not an array of 25 pointers to char.

2. Change

   char car;
   

   to

   int car;
   

   as getchar() returns an int, not a char.

3. Change

   scanf("%[^\n]s", &str);
   

   to

   scanf( "%24[^\n]", str);
   

   which tells scanf to

   1. Ignore all whitespace characters, if any.
   2. Scan a maximum of 24 characters (+1 for the Nul-terminator '\0') or until a \n and store it in str.

4. Change

   printf("\nThe sentence is %s, and the character is %s\n", str, car);
   

   to

   printf("\nThe sentence is %s, and the character is %c\n", str, car);
   

   as the correct format specifier for a char is %c, not %s.

str is an array of 25 pointers to char, not an array of char. So change its declaration to

char str[25];

And you cannot use scanf to read sentences--it stops reading at the first whitespace, so use fgets to read the sentence instead.

And in your last printf, you need the %c specifier to print characters, not %s. You also need to flush the standard input, because there is a '\n' remaining in stdin, so you need to throw those characters out.

The revised program is now

#include <stdio.h>    
void flush();
int main()
{
    char str[25], car;

    printf("Enter a character\n");
    car = getchar();

    flush();

    printf("Enter a sentence\n");
    fgets(str, 25, stdin);

    printf("\nThe sentence is %s, and the character is %c\n", str, car);

    return 0;
}
void flush()
{
    int c;
    while ((c = getchar()) != '\n' && c != EOF)
        ;
}