Hexadecimal to ASCII in C++

HexToAscii.cpp

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

using namespace std;

int hexToInt(char c)
{
    int first = c / 16 - 3;
    int second = c % 16;
    int result = first*10 + second;
    if (result > 9) result--;
    return result;
}

int hexToLetter(char c, char d)
{
    int high = hexToInt(c) * 16;
    int low = hexToInt(d);
    return high+low;
}

int main()
{

    const char* hexChar = "0008706574756C61";
    int length = strlen(hexChar);
    char buf = 0;
    cout << "FROM HEX: \n\r";
    for(int i = 0; i < length; i++) {
        if(i % 2 != 0) {
            printf("%c", hexToLetter(buf,hexChar[i]));
            //Different output
            //cout << static_cast<char>(hexToLetter(buf,hexChar[i]));
        } else {
            buf = hexChar[i];
        }
    }
    cout << "\n";

    return 0;
}