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#include <string>
#include <vector>
#include <sstream>
#include <algorithm>
#include <iostream>
std::vector<std::string> split( const std::string & text , char delim ) {
std::istringstream istr { text } ;
std::vector<std::string> tokens ;
std::string word ;
while ( std::getline( istr , word , delim ) ) {
tokens.push_back( word ) ;
}
return tokens ;
}
std::string to_binary_string( int num ) {
std::string binary ;
while ( num != 0 ) {
int remainder = num % 2 ;
binary.append( std::to_string( remainder ) ) ;
num /= 2 ;
}
std::reverse( binary.begin( ) , binary.end( ) ) ;
return binary ;
}
//the Hamming distance is the difference in set bits between the orred
//and the anded bitwise combination of 2 integers
int hamming_dist( int a , int b ) {
int orred = a | b ;
int anded = a & b ;
std::string orstring { to_binary_string( orred ) } ;
std::string andstring { to_binary_string( anded ) } ;
auto orones = std::count( orstring.begin( ) , orstring.end( ) , '1' ) ;
auto andones = std::count( andstring.begin( ) , andstring.end( ) ,
'1' ) ;
return ( static_cast<int>( orones ) - static_cast<int>( andones ) ) ;
}
std::vector<std::vector<int>> create_two_combinations( const
std::vector<int> & numbers ) {
int len = static_cast<int>( numbers.size( ) ) ;
std::vector<std::vector<int>> combis_of_two ;
for ( int i = 0 ; i < len - 1 ; i++ ) {
std::vector<int> nums ;
nums.push_back( numbers[i] ) ;
for ( int j = i + 1 ; j < len ; j++ ) {
nums.push_back( numbers[j] ) ;
combis_of_two.push_back( nums ) ;
nums.pop_back( ) ;
}
}
return combis_of_two ;
}
int main( ) {
std::cout << "Enter some integers separated by blanks!\n" ;
std::string line ;
std::getline( std::cin , line ) ;
auto tokens { split( line , ' ' ) } ;
std::vector<int> numbers ;
for ( auto s : tokens )
numbers.push_back( std::stoi( s ) ) ;
int sum = 0 ;
auto combis { create_two_combinations( numbers ) } ;
for ( auto vec : combis ) {
sum += hamming_dist( vec[0] , vec[1] ) ;
}
std::cout << sum << '\n' ;
return 0 ;
}
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