C / C++ / MFC

Rajesh R Subramanian wrote:

You could use strcat()[^] to concatenate strings.

sampath-padamatinti wrote:

Actually my requirement is "not use the strcat() function".

char* concat(const char* c1, const char* c2)

sampath-padamatinti wrote:

I am unable to solve this one. Please give me the approach

char * concat(const char * c1, const  char * c2)
{
  size_t size[2] = {strlen(c1), strlen(c2)};
  char * c = new char[size[0]+size[1]+1];
  strcpy(c, c1);
  strcpy(c+size[0],c2);
  return c;
}

char * concat(const char * c1, const char * c2)
{
  size_t len=0;
  char * c;
  const char *p;
  p = c1;
  while (*p++) len++;
  p = c2;
  while (*p++) len++;
  c = new char[len+1];
  p=c1;
  while (*c=*p++) c++;
  p=c2;
  while (*c++=*p++) ;  
  return (c-len-1);
}

void main()
{
  const char * str1 = "hello, ";
  const char * str2 = "folks!";
  char * result = concat(str1, str2);
  printf("%s\n", result);
  delete [] result;
}

char* concat(const char* c1, const char* c2)
{
	int size1 = 0, size2 = 0;

	for (int i = 0; c1[i] != '\0'; i++)
		size1++;
	for (int j = 0; c2[j] != '\0'; j++)
		size2++;

	char* result = new char[size1+size2];

	for(int i=0; i<size1; i++)
	{
		result[i] = c1[i];
	}

	for(int j = 0; j <= size2; j++)
	{
		result[size1+j] = c2[j];
	}

	result[size1+size2] = 0;

	return result;
}

sampath-padamatinti wrote:

return c3

sampath-padamatinti wrote:

Please tell me how to concat(add) two char*.

char *c3 = c1;
  
while (*c3)
    c3++;
  
while (*c3++ = *c2++)
    ;

DavidCrow wrote:

Something like:

char *c3 = c1;

while (*c3)
c3++;

while (*c3++ = *c2++)
;

char * concat( char * c1, const char * c2)
{
  char *c3 = c1;

  while (*c3)
    c3++;

  while (*c3++ = *c2++)
    ;
  return c1;
}

#include <stdio.h>
void main()
{
  char buf[100];
  sprintf(buf, "hello");
  char * str = " folks!";
  printf("%s\n", concat(buf, str));
}