Question

#include <iostream> #include <stdlib.h> #include <stdio.h> #include <cstring> using namespace std; /I Copy n characters from the source to the destination. 3 void mystrncpy( ???) 25 26 27 28 29 11- 30 Find the first occurrance of char acter c within a string. 32 ??? mystrchr???) 34 35 36 37 38 39 / Find the last occurrance of character c within a string. 40 II 41 ??? mystrrchr ???) 42 43 45

Use C++

Answer 1

The code is commented and variables are named accordingly.

Code:

#include <iostream>
#include <stdlib.h>
#include <stdio.h>
#include <cstring>

using namespace std;

// Copy n character from the source to destiation

void mystrncpy(char* destination, char* source, int num){

for(int i=0;i<num&&source[i]!='\0';i++)

destination[i]= source[i];

}

char *mystrchr(char* source, char c){

for(int i=0;source[i]!='\0';i++)

if(source[i]==c)

return (source+i);

return NULL;

}

char *mystrrchr(char* source, char c){

char *pChar= NULL;

for(int i=0;source[i]!='\0';i++)

if(source[i]==c)

pChar= (source+i);

return pChar;

}

int main() {

char userInput[81]; // User input to be manipulated
char *pChar = NULL; // Pointer to the result for some of the string function
  
cout<< "Provide a line of input: ";
fgets(userInput, 81, stdin);
  
// Stage 1: implement mystrncpy
int numberOfCharacters;
char destination[81];
  
cout<< "Enter number of characters to be copied: ";
cin>>numberOfCharacters;
mystrncpy(destination,userInput,numberOfCharacters);
cout<< "The resulting string is: "<< destination <<endl <<endl;
  
// Stage 2: implement mystrchr
cout<< "Enter the character to be found: ";
char c;
cin>>c;
pChar = mystrchr(userInput,c);
if(pChar==NULL){

cout<<c<<" Not Found!";

}
else{

// Update pChar from pChar - userInput to get position instead of the result that we are getting

cout<<"Found: "<<pChar<<endl;

}
  
// Stage 3: implement mystrrchr
cout<< "Enter the character to be reverse-found: ";

cin>>c;
pChar = mystrrchr(userInput,c);
if(pChar==NULL){

cout<<c<<" Not Found!";

}
else{

// Update pChar from pChar - userInput to get position instead of the result that we are getting

cout<<"Found: "<<pChar<<endl;

}
return 0;

}

Code Screenshot:

1 #include <iostream» 2 #include <stdlib.h> #include <stdio.h> 4 #include <CString> 6 using namespace std; 8 // Copy n character from the source to destiation 10 void nystrncpy (char destination, char* source, int num) for(int i-0inum&&source i]-'10';i++) 12 13 14 15 char *nystrchr(char* source, char c) 16 17 18 19 20 21 22 char *nystrrchr (char source, char c) 23 24 25 26 27 28 destination[i]-source[i]; for(int i-0;source[i]-0' ;i++) if (source[i]-c) return (source+i); return NULL char pChar- NULL for(int i-0;source[i]-0' ;i++) if (source[i]-c) pChar- (source+i); return pChar; 30 int main() 31 32 char userInput [81]; //User input to be manipulated char ·pchar -NULL; // Pointer to the result for some of the string function 34 35 cout<< "Provide a line of input: "; (userInput, 81, stdin);

36 37 38 39 40 41 42 43 /Stage 1: implement mystrncpy int numberOfcharacters; char destination[81]; cout<< "Enter number of characters to be copied: "; cin> numberofCharacters; mystrncpy (destination,userInput,numberofCharacters); cout<< "The resulting string is: "<< destination <<endl <endl; 45 46 47 48 49 50 51 52 53 54 //Stage 2: implement mystrchr cout<< "Enter the character to be found:"; char c; pChar nystrchr(userInput,c); if (pchar==NULL){ cout<<c<<" Not Found!" else cout<<"Found: "<pChar<endl; 56 57 58 59 60 61 62 63 64 65 //Stage 3: implement mystrrchr cout<< "Enter the character to be reverse-found:"; pChar mystrrchr(userInput,c); if (pCharNULL)[ else return ; cout<<c<<" Not Found!" cout<<"Found: "<pChar<endl; 67 68 69 70

Output:

Provide a line of input: Hello World Enter number of characters to be copied: 7 The resulting string is: Hello W Enter the character to be found: 1 Found: 1lo Worlo Enter the character to be reverse-found: o Found: orld