Please Help With Changing Case Program

I need to create a program for my friend that accepts a string from the user (not from the command line) and displays:

-The string using upper-case letters, e.g. all lower-case letters are converted to upper-case letters

-The string using lower-case letters, e.g. all upper-case letters are converted to lower-case letter.

-The string where the first letter of each word is upper-case and all other letters in the word are lower-case.

-The string in "camel case", i.e. the first letter in the string is lower case, followed by alternating upper and lower case letters.

-And that's it :P

Here’s what I have so far, I'm completely lost now :*( if anyone could help me finish this I'd greatly appreciate it. )) also I don't want to use string commands, too easy :P

Code:

void toUpper(char *str);
void toFirstCap(char *str);
void toCamelCase(char *str);

int main(int argc, char **argv)
{ 

char sentence[256]; 
char ch; int i = 0;
printf("Enter a string: ");
gets(sentence);


printf("\n%s\n",sentence);
toUpper(sentence);


printf("\nUpper case: %s\n",sentence);
toFirstCap(sentence);


printf("\nFirstCap case: %s\n",sentence);
toFirstCapSmartWay(sentence);


printf("\nFirstCap case: %s\n",sentence);
system("pause");
}


void toUpper(char *str)
{
while(*str != '\0')
{
if(*str >= 'a' && *str <= 'z')
/* CHECK whether the current character is a lower case alphabet */
{ *str -= 'd' - 'D';
} str++; }
}

void chngCaseSingleCharacter(char *str, int cAse)
{
cAse = 1 to covert into lower
cAse = 2 to covert into upper */
if(cAse == 2)
{ if(*str >= 'a' && *str <= 'z')
/* CHECK whether the current character is a lower case alphabet */
{
*str -= 'd' - 'D'; /* OR *str = *str - 32;}
}
else if(cAse == 1)
{ if(*str >= 'A' && *str <= 'Z')
/* CHECK whether the current character is an upper case alphabet */
{ 
*str += 'd' - 'D'; /* OR *str = *str + 32; WHY? WHAT?*/ }
}
}


void toFirstCap(char *str)
{
char b;
while( (b = *str++) != '\0')
{ if(b == ' ' || b == '\t')
if(*str >= 'a' && *str <= 'z')
{ *str -= 'd' - 'D'; }
} else
{
if(*str >= 'A' && *str <= 'Z') 
{
*str += 'd' - 'D'; }
}
}
}



void toFirstCapSmartWay(char *str)
{
char b; while( (b = *str++) != '\0') 
{ if(b == ' ' || b == '\t') {
chngCaseSingleCharacter(str, 2);
}
else {
chngCaseSingleCharacter(str, 1);
}
}
}



void toCamelCase(char *str)
{ /* char last = 'A'; // or some upper case letter; this serves as a
// tracker to the case of thelast alphabet written read char one by one till end of string
// USINg a loop
{ 
if(curr char is lower case)
{
if (last is lower case)
{
convert curr to upper case
last = curr
}
//lower case
}
else if(curr char is upper case)
{
.... similar to above
}
read the next character
} */
}

Here’s what I have so far, I'm completely lost now

A quick glance at the code: everything you have so far works, right? So you just need some direction for toCamelCase?

Pseudo code:

Code:

int current_case = 2;

while(current_char) {
     if (current_char is a letter) {
          chngCaseSingleLetter(current_char, current_case);
          [change current case to 2 if it's 1, or to 1 if it's already 2]
     }
}

Note: I'd suggest using 0 for lower case and (not 0) for upper case, then you can write the current_case changing code like this:

Code:

current_code = 1;
current_code = !current_code; //now current_code = 0
current_code = !current_code; //now current_code != 0

Code:

*str += 'd' - 'D'; /* OR *str = *str + 32; WHY? WHAT?*/

'd' - 'D' = 32. It's just a simple substitution. But 'd' - 'D' is probably better in this case - both are handled by the preprocessor, and 'd' - 'D' better explains what you're trying to do.

I figured I'd post the entire working code so you can see whats wrong. I've been trying to get "toLower" to work, but every way i use it, it just messes up the rest of them. I want it to display the sentence, then lowercase, then upper, then first case, then camel. i got the sentence, upper and first case to work. the other two i cant. please see if you can fix it, i feel retarded lol....

Code:

#include <stdio.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>


void toUpper(char *str);
void toFirstCap(char *str);
void toCamelCase(char *str);

int main(int argc, char **argv)
{ 

char sentence[256]; 
char ch; int i = 0;
printf("Enter a string: ");
gets(sentence);

printf("\nYour Sentence:%s\n",sentence);
toUpper(sentence);

printf("\nUpper case: %s\n",sentence);
toFirstCap(sentence);

printf("\nFirstCap case: %s\n",sentence);
toFirstCap(sentence);

system("pause");
}


void toUpper(char *str)
{
while(*str != '\0')
{
if(*str >= 'a' && *str <= 'z')
{ *str -= 'd' - 'D';
} str++; }
}


void chngCaseSingleCharacter(char *str, int cAse)
{
if(cAse == 2)
{ 
if(*str >= 'a' && *str <= 'z')
{
*str -= 'd' - 'D';
}
else if(cAse == 1)
{
if(*str >= 'A' && *str <= 'Z')
{ 
*str += 'd' - 'D';
}}}}



void toFirstCap(char *str)
{
char b;
while( (b = *str++) != '\0')
{ 
if(b == ' ' || b == '\t')
{
if(*str >= 'a' && *str <= 'z')
{ *str -= 'd' - 'D'; }
} 
else
{
if(*str >= 'A' && *str <= 'Z') 
{
*str += 'd' - 'D'; }
}
}
}


void toFirstCapSmartWay(char *str)
{
char b; while( (b = *str++) != '\0') 
{ if(b == ' ' || b == '\t') {
chngCaseSingleCharacter(str, 2);
}
else {
chngCaseSingleCharacter(str, 1);
}
}
}


//void toCamelCase(char *str)
//{
//{ 
//if(curr char is lower case)
//{
//if (last is lower case)
//{
//convert curr to upper case
//last = curr
//}
//}