adevtnofcodeDay3.cpp

#include <string>
#include <array>
#include <iostream>
void naive_solution(std::string &left, std::string &right)
{
    for(int i = 0; i < right.length(); i++)
    {
        //to check if the given character in the right matches any character in the left
        for(int j = 0; j < left.length(); j++)
        {
            if(right[i] == left[j])
            {
                std::cout<<"naive_solution The matching char is: "<<(right[i])<<"\n";
                return;
            }
        }
    }
}
bool binary_search(char element, std::string search_string)
{
    int start = 0, end = search_string.length() - 1;
    int middle = (start + end) / 2;
    while(start != middle)
    {
        if(search_string[middle] > element)
            end = middle - 1;
        else if(search_string[middle] < element)
            start = middle;
        else
            break;
        middle = (start + end) / 2;
    }
    return element == search_string[middle];
}
void binary_search_solution(std::string &left, std::string &right)
{
    //first sort left array
    std::sort(left.begin(), left.end());
    for(int i = 0; i < right.length(); i++)
    {
        //to check if the given character in the right matches any character in the left
        //search for element in sorted left array
        if(binary_search(right[i], left))
        {
            std::cout<<"bin search The matching char is: "<<(right[i])<<"\n";
            return;
        }
    }
}
int hash(char c)
{
    return c - 64;
}
void hash_set_solution(std::string &left, std::string &right)
{
    std::array<bool, 64> hash_set  = {0};
    for(int i = 0; i < left.length(); i++)
    {
        const char element = left[i];
        const int hash_code = hash(element);
        hash_set[hash_code] = true;
    }
    char solution = 0;
    for(int i = 0; i < right.length(); i++)
    {
        //to check if the given character in the right matches any character in the left
        if(hash_set[hash(right[i])])
        {
            std::cout<<"hash set The matching char is: "<<(right[i])<<"\n";
            return;
        }
    }
}
int main(int argc, char** argv)
{
    if(argc < 2)
    {
        std::cout<<"Please provide an input command line parameter";
    }
    std::string input = argv[1];
    std::string left = input.substr(0, input.length() / 2);
    std::string right = input.substr(input.length() / 2, input.length());
    std::cout<<"left: "<<left<<" right: "<<right<<"\n";
    naive_solution(left, right);
    hash_set_solution(left, right);
    binary_search_solution(left, right);
    return 0;
}