Thread: cipher program need alil help

Code:

	scanf("%s",&buff);

Getting input this way will stop at the first whitespace character. Try using fgets() instead.

Code:

// Capital A - Z 
if(unencrypt >= 'A' && unencrypt <= 'Z') 
{

Try isupper(), in <ctype.h>. There's an islower() as well.

haha yeah i fixed it. Ive been trying to reset the shift value for every word entered. This is what i have so far but it isnt working.

Code:

 

#include <stdio.h>  
#include <string.h> 
 
// Declare the function 
char ShiftCharacter(char unencrypt,int shift_value,int offset); 
 
 
int main(int argc, char* argv[]) 
{ 
 
	char buff[1024];  
	int shift_value;  
	int encrypt_text_length; 
	int i; 
	int x; 
	int y = 0; 
 
	// Say hello  
	puts("**initializing.....**\n\n**linking..........**\n\n");  
	puts("Welcome agent Brown\n\n");  
	puts("You have accessed the Caesar Cipher program\n\n");  
	puts("Please enter the text you wish to encrypt: "); 
 
	// Get input from the user 
	// It is possible that the user may exceed our allocated space. 
	// We could address that but it would cloud the issue. TODO: for later 
	 fgets(buff, sizeof buff, stdin);   
 
	puts("\nEnter your encryption shift value (anything from +-1 to 25): ");  
	scanf("%d",&shift_value);  
 
	// We now have a string and a shift value 
	// TODO: Check for empty string and out of range value 
 
 
	// Determine how long the string is 
	encrypt_text_length = strlen(buff); 
 
	// Encrypted the text 
	for(i = 0; i < encrypt_text_length; i++) 
	{ 
		buff[ i] = ShiftCharacter(buff[ i],shift_value,i); 
	}

 
// Encrypted the text  
	for(x = 0; x < encrypt_text_length; x++)  
	{  
     // if the current character is a space reset the offset to zero 
     // otherwise add one to the offset 
     if(buff[i] == ' ') 
     { 
          y = 0; 
     } 
     else 
     { 
          y++; 
     } 
 
     buff[i] = ShiftCharacter(buff[i],shift_value,i);   
	}

 
	// Display the encrypted text for the user 
	printf("\nYour encrypted text is: %s\n",buff);  
 
 
	return 0; /* indicate successful completeion */  
} 
 
 
// This function will shift the character by the determined amount 
// For our purpose we are only concerned with the letters a - z 
char ShiftCharacter(char unencrypt,int shift_value,int offset) 
{ 

int alphanumber; // The character as a number ( A = 1, B = 2, Z = 26 etc.)
char encrypted_char = unencrypt;
 
// Capital A - Z 
if(unencrypt >= 'A' && unencrypt <= 'Z') 
{ 
	alphanumber = unencrypt - 'A'; 
	alphanumber += shift_value + offset; 
	alphanumber = (alphanumber % 26); 
	encrypted_char  = (char)(alphanumber + 'A'); 
 
} 
 
// Lowercase a - z 
else if(unencrypt >= 'a' && unencrypt <= 'z') 
{ 
	alphanumber = unencrypt - 'a'; 
	alphanumber += shift_value + offset; 
	alphanumber = (alphanumber % 26); 
	encrypted_char  = (char)(alphanumber + 'a'); 
} 
 
return encrypted_char; 
 
}