Wsrtjtyk

Ok a few things: gets is unsafe and should be replaced with fgets(input, sizeof(input), stdin) so that you don't get a buffer overflow.

Next, to compare strings, you must use strcmp, where a return value of 0 indicates that the two strings match. Using the equality operators (ie. !=) compares the address of the two strings, as opposed to the individual chars inside them.

And also note that, while in this example it won't cause a problem, fgets stores the newline character, 'n' in the buffers also; gets() does not. If you compared the user input from fgets() to a string literal such as "abc" it would never match (unless the buffer was too small so that the 'n' wouldn't fit in it).

EDIT: and beaten by the super fast Mysticial once again.

You can't compare arrays directly like this

array1==array2

You should compare them char-by-char; for this you can use a function and return a boolean (True:1, False:0) value. Then you can use it in the test condition of the while loop.

Try this:

#include <stdio.h>

int checker(char input,char check);

int main()

{

    char input[40];

    char check[40];

    int i=0;

    printf("Hello!nPlease enter a word or character:n");

    scanf("%s",input);

    printf("I will now repeat this until you type it back to me.n");

    scanf("%s",check);



    while (!checker(input,check))

    {

        printf("%sn", input);

        scanf("%s",check);

    }



    printf("Good bye!");



    return 0;

}



int checker(char input,char check)

{

    int i,result=1;

    for(i=0; input[i]!='' || check[i]!=''; i++) {

        if(input[i] != check[i]) {

            result=0;

            break;

        }

    }

    return result;

}

Use strcmp.

This is in string.h library, and is very popular. strcmp return 0 if the strings are equal. See this for an better explanation of what strcmp returns.

Basically, you have to do:

while (strcmp(check,input) != 0)

or

while (!strcmp(check,input))

or

while (strcmp(check,input))

You can check this, a tutorial on strcmp.

Whenever you are trying to compare the strings, compare them with respect to each character. For this you can use built in string function called strcmp(input1,input2); and you should use the header file called #include<string.h>

Try this code:

#include<stdio.h> 

#include<stdlib.h> 

#include<string.h>  



int main() 

{ 

    char s="STACKOVERFLOW";

    char s1[200];

    printf("Enter the string to be checkedn");//enter the input string

    scanf("%s",s1);

    if(strcmp(s,s1)==0)//compare both the strings  

    {

        printf("Both the Strings matchn"); 

    } 

    else

    {

        printf("Entered String does not matchn");  

    } 

    system("pause");  

} 

Unfortunately you can't use strcmp from <cstring> because it is a C++ header and you specifically said it is for a C application. I had the same problem, so I had to write my own function that implements strcmp:

int strcmp(char input, char check)

{

    for (int i = 0;; i++)

    {

        if (input[i] == '' && check[i] == '')

        {

            break;

        }

        else if (input[i] == '' && check[i] != '')

        {

            return 1;

        }

        else if (input[i] != '' && check[i] == '')

        {

            return -1;

        }

        else if (input[i] > check[i])

        {

            return 1;

        }

        else if (input[i] < check[i])

        {

            return -1;

        }

        else

        {

            // characters are the same - continue and check next

        }

    }

    return 0;

}

I hope this serves you well.

    #include<stdio.h>

    #include<string.h>

    int main()

    {

        char s1[50],s2[50];

        printf("Enter the character of strings: ");

        gets(s1);

        printf("nEnter different character of string to repeat: n");

        while(strcmp(s1,s2))

        {

            printf("%sn",s1);

            gets(s2);

        }

        return 0;

    }

This is very simple solution in which you will get your output as you want.