C++: Basic example of template and std libs.

CPP elementary.cpp

#include <vector> 
#include <string> 
#include <iostream> 
#include <algorithm> 
using namespace std; 

template <typename T> 
void print(T element) { 
	cout << element << ' '; 
} 

int main() { 
	vector< char > v(5,'b');	// ={'b','b','b','b','b'}; 
	string s("ccccc"); 
	 
	vector< char > v2 = v; 
	v.push_back('2'); 

	cout << "Posledni prvek z v2:\t" << v2[ v2.size()-1 ] << endl; 	// out: b 

	for_each(v.begin(), v.end(), print<char>);	// out: b b b b b 2 
	cout << endl; 
} 


struct hover {
	int priority;
	char pismeno;

	hover(char pis, int pr) {
		pismeno = pis;
		priority = pr;
	}
	
	bool operator< (const hover& druhy) const {
		return priority < druhy.priority;
	}
};

struct lessHover {
	bool operator() (const hover& prvni, const hover& druhy) const {
		return prvni.priority < druhy.priority;
	}
};

struct greaterHover {
	bool operator() (const hover& prvni, const hover& druhy) const {
		return prvni.priority > druhy.priority;
	}
};

template<typename T>
void print(T element) {
	cout << element << ' ';
}
template<>
void print<hover>(hover element) {
	cout << element.pismeno << ' ';
}

int main()
{
	hover h1('a',1);
	hover h2('b',2);
	hover h3('w',0);

	if( h1 < h2 ) { cout << "true" << endl;} // out: true
	
	set< hover, lessHover > mn;
	mn.insert( h1 );
	mn.insert( h2 );
	mn.insert( h3 );

	for_each( mn.begin() , mn.end(), print<hover> );
	cout << endl;		// out: w a b

	set< hover, greaterHover > mn2;
	mn2.insert( h1 );
	mn2.insert( h2 );
	mn2.insert( h3 );

	for_each( mn2.begin() , mn2.end(), print<hover> );
	cout << endl;		// out: b a w

	priority_queue<hover,vector<hover>,lessHover> fronta;
	fronta.push(h1);
	fronta.push(h2);
	fronta.push(h3);

	while( ! fronta.empty() ) {
		cout << fronta.top().pismeno << ' ';
		fronta.pop();
	}		// out: b a w
}