#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <fstream>

using namespace std;

// here's the functor definition of the comparison operator
class sizesortT {
public:
	bool operator()(const string s1, const string s2) const {
		return s1.length()<s2.length()
			|| s1.length()==s2.length() && s1<s2;
	}
};

// here's the function (or fn ptr) method:
bool sizesortfn(const string s1, const string s2) {
	return s1.length()<s2.length()
		|| s1.length()==s2.length() && s1<s2;
}

int main(int argc, char **argv) {
	ifstream f("words");
	vector<string> words;
	while(!f.eof()) {
		string w;
		f >> w;
		words.push_back(w);
	}
	//sort(begin(words),end(words));  // sort w/ standard cmp
	//sort(begin(words),end(words),sizesortT()); // sort w/ new cmp as functor
	//sort(begin(words),end(words),sizesortfn); // sort w/ new cmp as function
	int cmpcount =0;
	// sort with new cmp as lambda (and a counter for # of cmps needed)
/*
	sort(begin(words),end(words),
		[&cmpcount](const string s1, const string s2) {
			cmpcount++;
			return s1.length()<s2.length()
				|| s1.length()==s2.length() && s1<s2;
		});
*/
	// same, but saving cmp lambda expression to use in multiple spots
	auto cmpcountfn = [&cmpcount](const string s1, const string s2) {
			cmpcount++;
			return s1.length()<s2.length()
				|| s1.length()==s2.length() && s1<s2;
		};
	// sort 1st time:
	sort(begin(words),end(words),cmpcountfn);
/*
	for(auto &w : words) 
		cout << w << endl;
*/
	cout << "needed " << cmpcount << " compares" << endl;
	cout << "for " << words.size() << " words" << endl;
	cout << "upon resort..." << endl;
	cmpcount = 0;
	// sort 2nd time:
	sort(begin(words),end(words),cmpcountfn);
	cout << "needed " << cmpcount << " compares" << endl;
	cout << "for " << words.size() << " words" << endl;
}