/* Code for exercise 6.13. |  | "C++ Solutions--Companion to The C++ Programming Language, Third Edition" | by David Vandevoorde; Addison-Wesley 1998; ISBN 0-201-30965-3. | | Permission to use, copy, modify, distribute and sell this software | and its documentation for any purpose is hereby granted without fee. | The author makes no representations about the suitability of this | software for any purpose.  It is provided "as is" without express or | implied warranty. `----------------------------------------------------------------------*/#include <stdio.h>#include <cstring>char* cat(char const *a, char const *b) {   std::size_t la = std::strlen(a);   char *s = new char[la+std::strlen(b)+1];   std::strcpy(s, a);   std::strcpy(s+la, b);   return s;}void concatenate(char const *a, char const *b, char *dest) {   while (*a!='\0') *dest++ = *a++;   while (*b!='\0') *dest++ = *b++;   *dest = '\0';}int main() {   char *result1 = cat("C++ ", "Programming");   printf("%s\n", result1);   delete[] result1; // New is done in "cat)" function   char result2[80];   concatenate("Four ", "Seasons", result2);   printf("%s\n", result2);}