Lab #12. C-style string processing in functions

Lab #12.1. String copying

Function strcpy() available in <cstring> library – copies the contents of source string src to destination string dest (lab11.1.cpp).

#include <iostream>

using namespace std;

char *strcpy2 (char *dest, const char *src)

{

// ADD CODE HERE

};

int main()

{

char s1[20] = "first";

char s2[20] = "second";

cout << s1 << endl << s2 << endl;

strcpy (s1, s2);

//strcpy2 (s1, s2);

cout << s1 << endl << s2 << endl;

return 0;

}

Create your own strcpy2() to imitate strcpy(). A technical feature of this function is to return the new string both through parameter and return statement (return type: char*):

char *strcpy2 (char *dest, const char *src)

const before the second parameters guarantees it not to be changed in the function.

It is assumed that there exists an array of enough size in memory for string dest.

A correct solution: lab11.1a.cpp.

Lab #12.2. String concatenation

Function strcat() (string concatenation) available in <cstring> library – copies all characters of source string src to the end of destination string dest (lab11.2.cpp).

#include <iostream>

using namespace std;

char *strcat2 (char *dest, const char *src)

{

// ADD CODE HERE

};

int main()

{

char s1[20] = "first";

char s2[20] = "second";

cout << s1 << endl << s2 << endl;

strcat (s1, s2);

//strcat2 (s1, s2);

cout << s1 << endl << s2 << endl;

return 0;

}

Create your own strcat2() to imitate strcat(). A technical feature of this function is to return the new string both through parameter and return statement (return type: char*):

char *strcat2 (char *dest, const char *src)

A correct solution: lab11.2a.cpp.

Lab #12.3. String comparison

Function strcmp() available in <cstring> library – compares two string on equality (lab11.3.cpp).

#include <iostream>

using namespace std;

int strcmp2 (const char *s1, const char *s2)

{

// ADD CODE HERE

};

int main()

{

char s1[20] = "first";

char s2[20] = "second";

char s3[20] = "first";

char s4[20] = "firs2";

cout << strcmp (s1, s2) << endl;

cout << strcmp (s2, s1) << endl;

cout << strcmp (s1, s3) << endl;

cout << strcmp (s1, s4) << endl;

/*cout << strcmp2 (s1, s2) << endl;

cout << strcmp2 (s2, s1) << endl;

cout << strcmp2 (s1, s3) << endl;

cout << strcmp2 (s1, s4) << endl;*/

return 0;

}

Create your own strcmp2() to imitate strcmp(). If both strings are equal, function returns 0, otherwise -1 or 1 (-1, if the first string is lexically smaller; 1, if greater):

char *strcmp2 (const char *s1, const char *s2)

A correct solution: lab11.3a.cpp.