Question

C++ code won't run. Fix?

//==========================================================
#include <conio.h> // For function getch()
#include <cstdlib> // For several general-purpose functions
#include <fstream> // For file handling
#include <iomanip> // For formatted output
#include <iostream> // For cin, cout, and system
#include <string> // For string data type

using namespace std; // So "std::cout" may be abbreviated to "cout"
//Converting hexadecimal to binary
int main()
{

   char binarynum[65], hexa[17];
   //Using long int because it has greater capacity
   long int i = 0;

   printf("Enter the hex value that needs to convert to binary: ");
   scanf_s("%s", hexa);
   printf("\n The converted hex value in binary is: ");
   while (hexa[i])
   {
       //These are the different cases for the binary that will be converted from hex. Case is the hex code and printf is the binary output.
       //It scans the inputs and then compares it to switch case that is below.
       switch (hexa[i])
       {
       case '0':
           printf("0000"); break;
       case '1':
           printf("0001"); break;
       case '2':
           printf("0010"); break;
       case '3':
           printf("0011"); break;
       case '4':
           printf("0100"); break;
       case '5':
           printf("0101"); break;
       case '6':
           printf("0110"); break;
       case '7':
           printf("0111"); break;
       case '8':
           printf("1000"); break;
       case '9':
           printf("1001"); break;
       case 'A':
           printf("1010"); break;
       case 'B':
           printf("1011"); break;
       case 'C':
           printf("1100"); break;
       case 'D':
           printf("1101"); break;
       case 'E':
           printf("1110"); break;
       case 'F':
           printf("1111"); break;
       case 'a':
           printf("1010"); break;
       case 'b':
           printf("1011"); break;
       case 'c':
           printf("1100"); break;
       case 'd':
           printf("1101"); break;
       case 'e':
           printf("1110"); break;
       case 'f':
           printf("1111"); break;
           //
       default:
           printf("\n Invalid hexa digit entered ", hexa[i]);
           return 0;
       }
       i++;
   }
  

       cout << "Press any key to exit ..." << endl;
       _getch();

   }

Answer 1

#include <conio.h> // For function getch()
#include <cstdlib> // For several general-purpose functions
#include <fstream> // For file handling
#include <iomanip> // For formatted output
#include <iostream> // For cin, cout, and system
#include <string> // For string data type

using namespace std; // So "std::cout" may be abbreviated to "cout"
//Converting hexadecimal to binary
int main()
{

char binarynum[65], hexa[17];
//Using long int because it has greater capacity
long int i = 0;

printf("Enter the hex value that needs to convert to binary: ");
scanf("%s", hexa); // Earlier scanf_s() was written which is incorrect as there is no method like scanf_s(), here scanf() is //used for input from console
printf("\n The converted hex value in binary is: ");
while (hexa[i])
{
//These are the different cases for the binary that will be converted from hex. Case is the hex code and printf is the binary output.
//It scans the inputs and then compares it to switch case that is below.
switch (hexa[i])
{
case '0':
printf("0000"); break;
case '1':
printf("0001"); break;
case '2':
printf("0010"); break;
case '3':
printf("0011"); break;
case '4':
printf("0100"); break;
case '5':
printf("0101"); break;
case '6':
printf("0110"); break;
case '7':
printf("0111"); break;
case '8':
printf("1000"); break;
case '9':
printf("1001"); break;
case 'A':
printf("1010"); break;
case 'B':
printf("1011"); break;
case 'C':
printf("1100"); break;
case 'D':
printf("1101"); break;
case 'E':
printf("1110"); break;
case 'F':
printf("1111"); break;
case 'a':
printf("1010"); break;
case 'b':
printf("1011"); break;
case 'c':
printf("1100"); break;
case 'd':
printf("1101"); break;
case 'e':
printf("1110"); break;
case 'f':
printf("1111"); break;
//
default:
printf("\n Invalid hexa digit entered %d ", hexa[i]);

// '%d' was missing in previous code, which is required to print hexa[i]
return 0;
}
i++;
}
  

cout << "\nPress any key to exit ..." << endl;
getch(); // there is no method like _getch(), which was there in previous code which is incorrect.

}

OUTPUT: