String Concatenate using non standard library functions...

[RC325]

I am attempting to write a concatenate function taking two chars in the form

sc1(char * s1, const char* s2);

The code for the function I have defined as:

char* stringCat1(char* s1, const char* s2){
	int i = 0, z = 0; 
	while (s1[i] != '\0'){
		i++; 
		}

	for (z = 0; s2[z] != '\0'; z++){ 		
			s1[i + z] = s2[z];
	}
return s1;	
}

This almost works - however when a concat strings are output I see something like:

stringCat1(s1, education): schooleducation╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠
╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠^_≈▬╝ⁿ1

Why do I see all the trailing chars? Please no responses telling me to implement standard library functions. Also, I know how to accomplish this with pointers.

Regards,

RC325

[kempofighter]

Show a main function that makes a call to the stringCat1 function. It appears that you end up with something that has no terminating NULL. Therefore when you try to print the data the code executes way beyond the end of the array until it happens to find a 0 in memory. After the second for loop you didn't bother to add a '\0' so you are returning a pointer to a non-null terminated character array.

[RC325]

Here is the main function requested:

View line numbers 21-24.

int main()
{
   char s1[ 100 ];
   char* s2 = "education";
   char* s3 = "school";
  
   // Test stringLength functions
   cout << "stringLength(" << s2 << "): "
        << stringLength1( s2 ) << endl;
   cout << "stringLength(" << s3 << "): "
        << stringLength2( s3 ) << endl;

   // Test stringCopy functions
   cout << "stringCopy1(s1, " << s2 << "): "
        << stringCopy1( s1, s2 ) << endl;
   cout << "stringCopy2(s1, " << s3 << "): "
        << stringCopy2( s1, s3 ) << endl;
 
   // Test stringCat functions
   cout << "stringCat1(s1, " << s2 << "): "
        << stringCat1( s1, s2 ) << endl;
   cout << "stringCat2(s1, " << s3 << "): "
        << stringCat2( s1, s3 ) << endl;
 
   system("pause");
   return 0; // indicates successful termination
} // end main

Regards,

RC325

[RC325]

Full code output:

stringLength(education): 9
stringLength(school): 6
stringCopy1(s1, education): education
stringCopy2(s1, school): school
stringCat1(s1, education): schooleducation╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠
╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠^_≈▬╝ⁿ1
stringCat2(s1, school): schooleducation╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠
╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠╠^_≈▬╝ⁿ1school
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