can someone reformat the code below based on the below assignment? Assignment Tr

Question

can someone reformat the code below based on the below assignment?

Assignment

Transposition Cipher (encrypt.c):
A very simple transposition cipher encrypt(S) can be described by the following rule:

If the length of S is 1 or 2, then encrypt(S) is S.

If S is a string of N characters s1 s2...sN and k=N/2, then
enc(S)=encrypt(sksk-1...s2s1)+encrypt(sNsN-1...sk+1)
where + indicates string cancatenation.
For example, encrypt("OK")="OK" and encrypt("12345678")="34127856".

Write a program to implement this cipher, given an arbitary text string from keyboard, up to 8192 characters. It's better to write a separate encryption function, similar to the following:

Input Format:
an abitary string (with the length up to 8192 characters).

Sample Input:
Test early and often!

Output Format
Line 1: One integer: the toal number of characters in the string.
Line 2: The enciphered string.

Sample Output:

Code

#include<stdio.h>

#include<string.h>

char* encrypt(char *string, size_t length);

void main()

{

char s[8192];char *enc;

printf("enter string: ");

scanf("%s",&s);

enc=encrypt(s,strlen(s));

printf("%s",enc);

}

char* encrypt(char *string, size_t length) {

int n=length;

int k=n/2;k--;

char encstr[length];int i;int c=0;

for(i=k;i>0;i=i-2)

{

encstr[c]=string[i-1];c=c+1;

encstr[c]=string[i];c=c+1;

}

for(i=n-1;i>k+1;i=i-2)

{

encstr[c]=string[i-1];c=c+1;

encstr[c]=string[i];c=c+1;

}

encstr[c]='';

char *enc;

enc=encstr;

return enc;

}

Explanation / Answer

#include<stdio.h>

#include<string.h>

char *encrypt(char *string, size_t length);

void main()
{

char s[8192];
char *enc;

printf("Enter string: ");

scanf("%[^ ]%*c",&s);
enc = encrypt(s,strlen(s));

printf("%s",enc);

}

char *encrypt(char *str, size_t length)
{
int n=length;

int k = n/2;
k--;

char *encstr = (char *)malloc(sizeof(char)*length);
int i;
int c=0;

for(i=k ; i>0 ; i=i-2)
{
encstr[c]=str[i-1];
c=c+1;
encstr[c]=str[i];
c=c+1;
}
if(i == 0){
encstr[c] = str[0];
c = c+1;
}
for(i=n-1;i>k+1;i=i-2)
{
encstr[c]=str[i-1];
c=c+1;

encstr[c]=str[i];
c=c+1;
}

encstr[c]='';

return encstr;
}

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