The match function is supposed to return true if and only if its two C-string ar

Question

  The match function is supposed to return true if and only if its two C-string arguments have exactly same text. Explain what the problems with the implementation of the function are, and show a way to fix them.

// return true if two C strings are equal
bool match(const char str1[], const char str2[])
{
bool result = true;
while (str1 != 0  &&  str2 != 0) // zero bytes at ends
{
if (str1 != str2) // compare corresponding characters
{
result = false;
break;
}
str1++; // advance to the next character
str2++;
}
if (result)  
{
result = (str1 == str2); // both ended at same time?
}
return( result );
}

int main()
{
char a[10] = "pointy";
char b[10] = "pointless";

if (match(a,b))
{
cout << "They're the same!" << endl;
}
}

Explanation / Answer

Hi, Please find my explanation and fixed code.

0 and '' are two different characters

and C-string end mark is : ''

So,instead of : while (str1 != 0 && str2 != 0)
It should be : while (*str1 != '' && *str2 != '')

this lien: str1 == str2 => compares the address of both string they point to,

Here we have to check whether both str1 and str2 pointing to '' character, so
it should be :
                   *str1 == *str2

Like this : str1 != str2
   should be also: *str1 != *str2

####################################

#include <iostream>
using namespace std;

// return true if two C strings are equal
bool match(const char str1[], const char str2[])
{
bool result = true;
while (*str1 != '' && *str2 != '') // zero bytes at ends
{
if (*str1 != *str2) // compare corresponding characters
{
result = false;
break;
}
str1++; // advance to the next character
str2++;
}

if (result)
{
result = (*str1 == *str2); // both ended at same time?
}
return( result );
}

int main()
{
char a[10] = "pointy";
char b[10] = "pointy";

if (match(a,b))
{
cout << "They're the same!" << endl;
}else{
   cout << "They are not same!" << endl;
}
}

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