Our Combination code in C++.
Combination Class Header File:
Combination Class File:
Main Class:
Try it out!
Combination Class Header File:
#pragma once
#include <string>
#include <vector>
using namespace std;
class Combination
{
public:
Combination();
virtual ~Combination();
// variables
vector<string> words;
unsigned short r; // min length of word
// functions
vector<vector<string>> possibleWordCombinations(vector<string>, unsigned short);
void progressiveCombination(void);
protected:
vector<vector<string>> comb_store;
private:
void repetitivePairing(vector<string>, unsigned);
unsigned int i;
};Combination Class File:
#include "stdafx.h"
#include "Combination.h"
Combination::Combination()
{
}
// point of entry
vector<vector<string>> Combination::possibleWordCombinations(vector<string> candidates, unsigned short dimension) {
words = candidates;
r = dimension;
comb_store = {};
i = 0;
// check for conformity
if (r <= 0 || r > words.size()) {
comb_store = {};
}
else if (r == 1) {
for (; i < words.size(); i++) {
comb_store.push_back({words[i]});
}
}
else {
progressiveCombination();
}
return comb_store;
}
// do combinations for all 'words' element
void Combination::progressiveCombination() {
// single member list
repetitivePairing({words[i]}, i + 1);
if (i + r <= words.size()) {
// move on to next degree
i++;
progressiveCombination();
}
}
// do all possible combinations for 1st element of this array
void Combination::repetitivePairing(vector<string> prefix, unsigned position) {
vector<string> * auxiliary_store;
auxiliary_store = new vector<string>[words.size() - position];
for (unsigned j = 0; position < words.size(); position++, j++) {
// check if desired -- r -- size will be realised
if (r - prefix.size() <= words.size() - position) {
auxiliary_store[j] = prefix;
auxiliary_store[j].push_back(words[position]);
if (auxiliary_store[j].size() < r) {
// see to adding next word on
repetitivePairing(auxiliary_store[j], position + 1);
}
else {
comb_store.push_back(auxiliary_store[j]);
}
}
}
delete[] auxiliary_store; // memory friendly
comb_store.shrink_to_fit();
}
Combination::~Combination()
{
}Main Class:
#include "stdafx.h"
#include "Combination.h"
#include <vector>
#include <iostream>
using namespace std;
int main()
{
vector<string> goods = { "Eno", "Chidi", "Olu", "Ahmed", "Osas", "Gbeda" };
Combination combo;
vector<vector<string>> result = combo.possibleWordCombinations(goods, 3);
// print choices and operation
cout << "\n[";
for (string choice : combo.words) {
cout << choice << "; ";
}
cout << "] combination " << combo.r << ":\n\n";
// print out combinations nicely
int i = 0;
for (vector<string> set : result) {
i++;
cout << i << ": ";
for (string member : set) {
cout << member << "; ";
}
cout << "\n";
}
cout << "\nNumber of ways is " << result.size() << ".";
return 0;
}Try it out!
Elegance (0.0)
