C++ Strings

cblue

I don't yet have a clear understanding of how to use the string class yet.

i'm stuck as how to get started. I have this program that wants you to use find, length and substr without any type of loop or switch to convewrt a string into it's pig latin equivalent. Assume the vowels are e i o u and you are to check for the irst occurence of a vowel if the first letter has vowel add way to the end otherwise continue checking for the first occurence of a vowel and if found move the letters to the end and add ay to the end.

for example: apple = appleway
strong = ongstray
Any help would greatly be appreciated

mondi

something like this:

(http://www.cplusplus.com - great place to learn standard functions)

#include <stdio.h> //IO functions
#include <string.h> // String library

void main ()
{

	char theString[100];	  // original string
	char pigLatin[100];		  // piglatin output
	char temp[100];		      // temp string
	char * chopper;			  // used to chop string up

	printf("Enter string: ");
	gets(theString);           // get a string from the keyboard

	char vowels[]= "aeiouAEIOU";	 // define vowels
	int checkString;				 // integer to hold position of first vowel
	checkString = strcspn (theString,vowels); // find first vowel

	if (checkString==0)				 // if first vowel is first letter
	{
		strcpy(pigLatin,theString);  // copy orginal string 
		strcat(pigLatin,"way\0");	 // append "way"
	}
	else							 // otherwise
	{
		strncpy(temp,theString,checkString); // copy letters before first vowel to temp string
		chopper=strtok(theString,temp);		 // chop off those letters
		strcpy(pigLatin,chopper);			 // copy the remaining string to pig latin
		strcat(pigLatin,temp);				 // append copied letters
		strcat(pigLatin,"ay\0");			 // append "ay"
	}

	printf("Pig Latin is: %s\n",pigLatin); // print and done.

}

edit:// this only works on single words btw, in order to make it work with sentences, use the same chopper code in a simple loop, and chop on " " (check the link for how to do this) and then pass each delimited string to the vowel check seperately.

m

cblue

thanks for the response, unfortunately in c++ i need to utilize the functions find, substr and lenght using the string class and suggestions how to use these to check each occurence of a vowel and then moving the charactersto the end of the string would greatly be appreciated

JB

ok, what you are going to do is use the .find function to check if that word has a vowel.

If it finds the letter you are looking for with the .find function it will return the index of the letter. Now you have to use the .substr from 0 to that index value returned to take off the front of the string and you can store that in a temporary string.

Use the index for the vowel and substring again to get the final part of the word and store that in another temporary string.

Finally, you can use + or .strcat to add the strings together and tack on the "way".

cblue

I understand what i need to do, the problem is trying to test each oocurence of the vowel.


for example say you have this:

int main()
{
string word;
int pos;
int position;
cout << " Enter A Word: ";
cin >> word;
pos = word.find("a");
if (pos != string::npos)
position = pos;
pos = word.find("e")
if(pos != string::npos)
if(pos < position)
position = pos;
}

this is the problem, it bombs once this is working i can use substr to chop the preciding letters off that are in front of the vowel i find.

mmonnin

Yeah what mondi used was a null-termined array which is kinda like a string.

cplusplus.com and the MSDN website can help you out.