Learning C++ Example Problems [closed] - c++

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I am currently going though the process of learning C++ though reading programming books. I understand the concept but find a few days after reading, the concepts start to drift from my memory.
The only thing that keeps them there is working through examples/questions.
Are there any good sites or books that can be recommend which give a large number of examples/questions to work through, with explanations of what each example should help you learn?

Answer 1

If your books don't give you tasks to chew on, get better books.
Look at those mentioned here.

Answer 2

This site and this site may be worth looking for you.

Answer 3

You're right. Reading books is not likely to help unless you practice what you learn.
You didn't say what kind of examples you need, and obviously it's important to choose examples which mean something to you - that is, applications which you can see the value of.
Can you suggest some topics which interest you? Like business applications or games, scientific or otherwise?

Answer 4

Just for coment, some examples, i trying add some code....
#include <iostream>
#include <string>
#include <list>
#include <vector>
#include <set>
#include <map>
#include <iterator>
#include <algorithm>
#include <iomanip>
#include <iostream>
using namespace std;
bool Porovnej(int &p1) {
if (p1 > 5)
{
return true;
}
return false;
}
struct osoba{
int vek;
string jmeno;
set<char> mnozinaPismen;
public:
void Vypis();
};
void osoba::Vypis() {
cout << vek << endl;
cout << jmeno << endl;
for (auto m : mnozinaPismen){
cout << m << endl;
}
cout << "" << endl;
};
int Vytrid(int &prvek) {
if(prvek !=30){
return prvek;
}
return -(prvek);
}
struct JaKralJeliman{
int vek;
string jmeno;
string titul;
public:
void Vypis();
};
void JaKralJeliman::Vypis() {
cout << vek << endl;
cout << titul << endl;
cout << jmeno << endl;
}
class Vytridit{
public:
int operator()(int &prvek) const{
if (prvek > 2) {
return prvek;
}
}
};
int Pricti(int &prvek){
prvek = prvek + 1;
return prvek;
}
class NasobeniHodnot {
private: int _hodnota;
public: NasobeniHodnot(int hodnota) :_hodnota(hodnota) {}
void operator() (int &prvek) const { prvek *= _hodnota; }
};
int GenerujPrvky(){
int prvek = 0;
prvek += rand();
return prvek;
}
class Pair {
private:
int _key, _value;
public:
int GetKey() const { return _key; }
int GetValue() const { return _value; }
void SetKey(int key) { _key = key; }
void SetValue(int value) { _value = value; }
};
istream& operator>>(istream &is, Pair &objekt) {
int cislo;
is >> cislo; /* Využiji již přetížených operátorů pro primitivní datové typy.*/
objekt.SetKey(cislo);
is >> cislo;
objekt.SetValue(cislo);
return is;
}
ostream& operator<<(ostream &os, const Pair &objekt) {
os << objekt.GetKey() << objekt.GetValue();
return os;
}
int main()
{
vector<int> v;
vector<int>::iterator it;
vector<int> v2(100);
vector<int> v3(10);
for (int i = 1; i < 10; i++)
{
v.push_back(i+1);
}
it = find(v.begin(), v.end(), 5);
cout << *it << endl;
back_inserter(v) = 30;
back_inserter(v) = 32;
back_inserter(v) = 32;
back_inserter(v) = 30;
back_inserter(v) = 30;
v.reserve(2 * v.size());
copy(v.begin(), v.end(), back_inserter(v));
copy(v.begin(), v.end(), ostream_iterator<int>(cout, " "));
// for_each(v.begin(), v.end(), ostream_iterator<int>(cout));
it = min_element(v.begin(), v.end());
it = max_element(v.begin(), v.end());
int pocetTricitek = count(v.begin(), v.end(), 30);
cout << "Pocet hodnoty 30 v kontejneru v je:" << pocetTricitek << endl;
cout << "Nejvetsi hodnota" << *it <<endl;
it = find_if(v.begin(), v.end()-1, Porovnej);
cout << "Hodnota iteratoru:" << *it << endl;
it = search_n(v.begin(), v.end()-1, 3, 32);
cout << "Hodnota iteratoru:" << *it << endl;
transform(v.begin(), v.end(), v2.begin(), Vytrid);
fill_n(v3.begin(), 5, 10);
replace(v.begin(), v.end(), 30, 1); //nahradí číslo 30 číslem 1
reverse(v.begin(), v.end());
rotate(v.begin(), v.begin() + 3, v.end());
sort(v.begin(), v.end());
//partial_sort(v.begin(), v.begin() + 10, v.end());
it = lower_bound(v.begin(), v.end(), 15); //>= než 15
vector<int> kolekce(10);
generate(kolekce.begin(), kolekce.end(), GenerujPrvky);
NasobeniHodnot nh(2);
for_each(kolekce.begin(), kolekce.end(), nh);
for_each(kolekce.begin(), kolekce.end(), NasobeniHodnot(2));
int c = 1000, b = 9;
cout << setw(3) << "b=" << b << endl << "c=" << c << endl;
cout << setw(3) << setfill('#') << hex << "c=" << c;
cout << endl;
Pair pair;
cin >> pair;
cout << "Objekt byl:" << endl << pair;
system("pause");
return 0;
}
/*String
string s = "ahoj Oldo";
string::size_type idx;
int pocet = 0;
string s2("Ahoj karle", 6);
cout << s2;
idx = s.find("o");
cout << "idx:" << idx << "string s:" << s << endl;
if (idx == std::string::npos) {
cout << "Není obsažen v řetězci";
} else{
cout << "Je obsažen v řetězci na pozici:" << idx;
}
--------------------//////////////---------------------------
Kontejnery:
string pole[] = { "2", "50" ,"99", "1000" };
list<string> seznam(pole, pole+sizeof(pole)/sizeof(pole[0]));
vector<string> vektorRetezcu;
vektorRetezcu.push_back("a");
vektorRetezcu.push_back("b");
vektorRetezcu.push_back("c");
vektorRetezcu.push_back("d");
vektorRetezcu.push_back("e");
vektorRetezcu.push_back("e");
vektorRetezcu.push_back("a");
list<string> seznam2(vektorRetezcu.begin(), vektorRetezcu.end());
for (auto s : seznam2)
{
cout << s << endl;
}
swap(seznam, seznam2);
for (auto s : seznam2)
{
cout << s << endl;
}
string s1 = "ahoj";
string s2 = "olda";
cout << s1 << s2 << endl;
swap(s1, s2);
cout << s1 << s2 << endl;
--------------------////////////-/////----------------
List
list<osoba> listOsob;
osoba clovek;
for (int i = 0; i < 3; i++)
{
cout << "Zadej cloveka:" << endl;
cin >> clovek.jmeno;
cin >> clovek.prijmeni;
cin >> clovek.vek;
listOsob.push_back(clovek);
}
for (auto osoby : listOsob)
{
cout << "Clovek cislo " << endl;
cout << osoby.jmeno << endl;
}
///////////////////////////////////////////////---------------------mnozicn
struct osoba{
int vek;
string jmeno;
set<char> mnozinaPismen;
public:
void Vypis();
};
void osoba::Vypis() {
cout << vek;
cout << jmeno;
for (auto m : mnozinaPismen)
{
cout << m << endl;
}
}
int main()
{
vector<osoba> vectorLidi;
osoba clovek;
for (int i = 0; i < 3; i++)
{
cin >> clovek.vek;
cin >> clovek.jmeno;
for (int i = 0; i < clovek.jmeno.length(); i++)
{
clovek.mnozinaPismen.insert(clovek.jmeno[i]);
}
vectorLidi.push_back(clovek);
}
for (auto v : vectorLidi)
{
v.Vypis();
}
system("pause");
return 0;
}
-----------------////////////-------------------
vector<osoba> vectorLidi;
osoba clovek;
for (int i = 0; i < 3; i++)
{
cin >> clovek.vek;
cin >> clovek.jmeno;
for (int i = 0; i < clovek.jmeno.length(); i++)
{
clovek.mnozinaPismen.insert(clovek.jmeno[i]);
}
vectorLidi.push_back(clovek);
}
cout << "Nacte no -------------" << endl;
for (auto v : vectorLidi)
{
v.Vypis();
}
*/