Basic C Question :(

[Odc]

Hi guys,

I'm trying to create a simple function that reverses a string without using any in-built functions. I have code that should work but it just crashes on the first loop. I have no idea whats wrong and its rather frustrating being such an easy problem! Any ideas?


#include <iostream>

void reverse(char *p)
{
char temp, *pCopy;
int i, j, sizeOfString;

sizeOfString = 0;
pCopy = p;

while(*pCopy != '\o') // Calculates size of p or pCopy
{
sizeOfString ++;
*pCopy ++;
}

for(i = 0, j = sizeOfString; i < j; i ++, j --) // Reverses the string
{
temp = p[i];
p[i] = p[j];
p[j] = temp;
}
}

int main()
{
char *testString = "Hello";

reverse(testString);

std::cout << testString << std::endl;

return 0;
}

[Odc]

I found the problem, you have to declare

char testString[] = "Hello";

instead.

[kalniel]

Yup. Strings are arrays of characters, and declaring arrays has slightly different nomenclature to declaring simple variables (and in your case you're initialising it at the same time as declaring it).

[TheAnimus]

Sounds like you fixed the problem, but just make sure your happy with the difference between a pointer and an array as I'm assuming this is school work!

That said the amount of times I screw something up because i'll be using < rather than >.....

[rovina123]

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

int main()
{
int i, totalCharacter, totalE;
char txt[301];

// Ask user to enter his/her sentence
printf("Type your sentence: ");
gets(txt);

// 1) Total characters in the sentence (spaces included)
for(totalCharacter = 0; totalCharacter < txt[totalCharacter]; totalCharacter++);
printf("Your sentence has %i characteres (including any spaces).\n\n", totalCharacter);

// 2) Total e's in the sentence
totalE = 0;
for(i = 0; i < totalCharacter; i++){
if(txt[i] == 'e')
totalE++;}
printf("There are %i 'e' in your sentence.\n\n", totalE);

// 3) Sentence with words reversed (INCOMPLETED!)
for(i = 0; i < totalCharacter; i++)



// 4) Sentence with letters AND words reversed (INCOMPLETED!)
for(i = 0; i < totalCharacter; i++)


system("PAUSE");
return 0;
}

[streetster]

you what?

[Steve7]

Rovina, can you please clarify your question? I don't get what you want to say?