assign

// assign a sequence to the list #include <iostream> #include <list> #include <algorithm> #include <iterator> using namespace std; int main () { int ary[]={1,2,3,4,5}; list<int> l; // assign to l the contains of ary l.assign(ary,ary+5); copy(l.begin(),l.end(), ostream_iterator<int>(cout," ")); cout << endl; // replace l for 3 copies of 100 l.assign(3,100); copy(l.begin(),l.end(), ostream_iterator<int>(cout," ")); cout << endl; return 0; } OUTPUT: // 1 2 3 4 5 // 100 100 100 back
// returns the last element #include <iostream> #include <list> #include <algorithm> #include <string> #include <iterator> using namespace std; template<class T, class D> class Member { public: Member(T t, D d) : name(t), sal(d) {} void print(); private: T name; D sal; }; template<class T, class D> void Member<T,D>::print() { cout << name << " " << sal << endl; } //-------------------------------------- int main () { typedef Member<string,double> M; list<M> l; l.push_back(M("Robert",60000)); l.push_back(M("Linda",75000)); list<M>::iterator It = l.begin(); cout << "Entire list:" << endl; while ( It != l.end() ) (It++)->print(); cout << endl; cout << "Return from back()" << endl; l.back().print(); return 0; } OUTPUT: // Entire list: // Robert 60000 // Linda 75000 // // Return from back() // Linda 75000 begin
// returns an iterator to the beginning #include <iostream> #include <list> #include <algorithm> #include <iterator> #include <numeric> using namespace std; int main () { list<int> l(5); iota(l.begin(),l.end(),1); list<int>::iterator It = l.begin(); while ( It != l.end() ) cout << *It++ << " "; cout << endl; // third element of the list It = l.begin()+2; cout << *It << endl; return 0; } OUTPUT: // 1 2 3 4 5 // 3 clear
// removes all elements #include <iostream> #include <list> using namespace std; int main () { list<int> l(5,10); cout << "Size of list = " << l.size() << endl; l.clear(); cout << "After l.clear() size of list = " << l.size() << endl; return 0; } OUTPUT: // Size of list = 5 // After l.clear() size of list = 0 empty
// true if the list is empty #include <iostream> #include <list> using namespace std; int main () { list<int> l; cout << "List is "; l.empty() ? cout << "" : cout << "not "; cout << "empty" << endl; l.push_back(100); cout << "List is "; l.empty() ? cout << "" : cout << "not "; cout << "empty" << endl; return 0; } OUTPUT: // List is empty // List is not empty end
// returns an iterator to the end #include <iostream> #include <list> #include <numeric> using namespace std; int main () { list<int> li(10); iota(li.begin(),li.end(),1); list<int>::iterator It = li.begin(); while ( It != li.end() ) cout << *(It++) << " "; cout << endl; return 0; } OUTPUT: // 1 2 3 4 5 6 7 8 9 10 erase
// erase an elemen #include <iostream> #include <list> #include <algorithm> #include <numeric> using namespace std; template <class T> void print (list<T>& l) { list<int>::iterator It = l.begin(); while ( It != l.end() ) { cout << *(It++) << " "; } cout << endl; } //===================== int main () { list<int> li(10); iota(li.begin(),li.end(),1); print(li); list<int>::iterator It; It = find(li.begin(),li.end(),6); // erase at the pos It li.erase(It); print(li); It = find(li.begin(),li.end(),4); // erase from beginning to the pos It li.erase(li.begin(),It); print(li); return 0; } OUTPUT: // 1 2 3 4 5 6 7 8 9 10 // 1 2 3 4 5 7 8 9 10 // 4 5 7 8 9 10 front
// returns the first element #include <iostream> #include <list> int main () { int ary[] = {1,2,3,4,5}; list li; for ( int i=0; i<5; i++ ) { li.push_front(ary[i]); cout << "front() : " << li.front() << endl; } return 0; } OUTPUT: // front() : 1 // front() : 2 // front() : 3 // front() : 4 // front() : 5 insert
// insert elements into the list #include <iostream> #include <list> #include <algorithm> #include <numeric> using namespace std; template <class T> void print (list<T>& l) { list<int>::iterator It = l.begin(); while ( It != l.end() ) { cout << *(It++) << " "; } cout << endl; } //==================================== int main () { list<int> li1(10,0); list<int> li2(5); list<int>::iterator It; iota(li2.begin(),li2.end(),1); cout << "li1 : "; print(li1); cout << "li2 : "; print(li2); It = li1.begin(); // value of 20 at the pos It li1.insert(++It,20); cout << "li1 : "; print(li1); // two value of 25 at the beginning li1.insert(li1.begin(),2,25); cout << "li1 : "; print(li1); // contents of li2 at the end of li1 li1.insert(li1.end(),li2.begin(),li2.end()); cout << "li1 : "; print(li1); return 0; } OUTPUT: // li1 : 0 0 0 0 0 0 0 0 0 0 // li2 : 1 2 3 4 5 // li1 : 0 20 0 0 0 0 0 0 0 0 0 // li1 : 25 25 0 20 0 0 0 0 0 0 0 0 0 // li1 : 25 25 0 20 0 0 0 0 0 0 0 0 0 1 2 3 4 5 max_size
// returns the maximum number of elements the list can hold #include <iostream> #include <list> int main () { list li(10); cout << "size() of li = " << li.size() << endl; cout << "max_size = " << li.max_size() << endl; return 0; } OUTPUT: // size() of li = 10 // max_size = 4294967295 merge
// merge two lists #include <iostream> #include <list> #include <algorithm> #include <iterator> using namespace std; int main () { int ary[] = {2,5,9,7,2,7,6,5}; list<int> list1(ary,ary+4); list<int> list2(ary+4,ary+8); cout << "list1 : "; copy(list1.begin(),list1.end(), ostream_iterator<int>(cout," ")); cout << endl; cout << "list2 : "; copy(list2.begin(),list2.end(), ostream_iterator<int>(cout," ")); cout << endl << endl; // you have to sort data before megring it list1.sort(); list2.sort(); list1.merge(list2); cout << "After \"list1.merge(list2)\" :" << endl; cout << "list1 : "; copy(list1.begin(),list1.end(), ostream_iterator(cout," ")); cout << endl; cout << "size of list2 = " << list2.size() << endl; cout << "list2 is " << (list2.empty() ? "" : "not ") << "empty" << endl; return 0; } OUTPUT: // list1 : 2 5 9 7 // list2 : 2 7 6 5 // // After "list1.merge(list2)" : // list1 : 2 2 5 5 6 7 7 9 // size of list2 = 0 // list2 is empty pop_back
// removes the last element #include <iostream> #include <list> #include <algorithm> #include <numeric> using namespace std; int main () { list<int> l(5); iota(l.begin(),l.end(),1); copy(l.begin(),l.end(), ostream_iterator<int>(cout," ")); cout << endl; while ( !l.empty() ) { l.pop_back(); copy(l.begin(),l.end(), ostream_iterator<int>(cout," ")); cout << endl; } return 0; } OUTPUT: // 1 2 3 4 5 // 1 2 3 4 // 1 2 3 // 1 2 // 1 pop_front
// removes the first element #include <iostream> #include <list> #include <algorithm> int main () { list<int> l(5,0); copy(l.begin(),l.end(), ostream_iterator<int>(cout," ")); cout << endl; cout << "Size of list = " << l.size() << endl; int size = l.size(); while ( !l.empty() ) { l.pop_front(); cout << "Size of list = " << l.size() << endl; } return 0; } OUTPUT: // 0 0 0 0 0 // Size of list = 5 // Size of list = 4 // Size of list = 3 // Size of list = 2 // Size of list = 1 // Size of list = 0 push_back
// add an element to the end of the list #include <iostream> #include <list> #include <iomanip> #include <string> using namespace std; template <class T> class Name { public: Name(T f, T l) : first(f), last(l) {} void print() { cout.setf(ios::left); cout << setw(15) << first.c_str() << last << endl; } private: T first, last; }; //========================================== int main () { typedef Name<string> N; typedef list<N> L; L l; L::iterator It; N n1(string("Albert"),string("Johnson")); N n2("Lana","Vinokur"); l.push_back(n1); l.push_back(n2); // unnamed object l.push_back(N("Linda","Bain")); It = l.begin(); while ( It != l.end() ) (It++)->print(); cout << endl; return 0; } OUTPUT: // Albert Johnson // Lana Vinokur // Linda Bain push_front
// add an element to the front of the list #include <iostream> #include <list> #include <iomanip> #include <string> using namespace std; template <class T> class Name { public: Name(T f, T l) : first(f), last(l) {} void print() { cout.setf(ios::left); cout << setw(15) << first.c_str() << last << endl; } private: T first, last; }; //========================================== int main () { typedef Name<string> N; typedef list<N> L; L l; L::iterator It; N n1(string("Albert"),string("Johnson")); N n2("Lana","Vinokur"); l.push_front(n1); l.push_front(n2); // unnamed object l.push_front(N("Linda","Bain")); It = l.begin(); while ( It != l.end() ) (It++)->print(); cout << endl; return 0; } OUTPUT: // Linda Bain // Lana Vinokur // Albert Johnson rbegin
// returns a reverse iterator to the beginning of the list #include <iostream> #include <list> #include <algorithm> #include <numeric> #include <iterator> using namespace std; int main () { list<int> l(10); iota(l.begin(),l.end(),1); copy(l.begin(),l.end(), ostream_iterator<int>(cout," ")); cout << endl; list<int>::reverse_iterator It = l.rbegin(); while ( It != l.rend() ) cout << *(It++) << " "; cout << endl; return 0; } OUTPUT: // 1 2 3 4 5 6 7 8 9 10 // 10 9 8 7 6 5 4 3 2 1 remove
// removes elements from the list #include <iostream> #include <list> #include <algorithm> #include <string> using namespace std; template <class T, class D> class Salary { public: Salary(T t) : id(t) {} Salary(T t,D d) : id(t), sal(d) {} void print () { cout << id << " " << sal << endl; } private: T id; D sal; friend bool operator == (const Salary& s1,const Salary& s2) { return s1.id == s2.id; } }; //========================================== int main () { typedef Salary<string,double> S; typedef list<S> L; L l; l.push_back(S("012345",70000.0)); l.push_back(S("012346",60000.0)); l.push_back(S("012347",72000.0)); L::iterator It = l.begin(); while ( It != l.end() ) (It++)->print(); cout << endl; S s("012345"); l.remove(s); It = l.begin(); while ( It != l.end() ) (It++)->print(); cout << endl; return 0; } OUTPUT: // 012345 70000 // 012346 60000 // 012347 72000 // // 012346 60000 // 012347 72000 remove_if
// removes elements conditionally #include <iostream> #include <list> #include <algorithm> OUTPUT: rend
// returns a reverse iterator to the start of the list #include <iostream> #include <list> #include <algorithm> #include <numeric> #include <iterator> using namespace std; int main () { list<int> l(10); iota(l.begin(),l.end(),1); copy(l.begin(),l.end(), ostream_iterator<int>(cout," ")); cout << endl; list<int>::reverse_iterator It = l.rbegin(); while ( It != l.rend() ) cout << *(It++) << " "; cout << endl; return 0; } OUTPUT: // 1 2 3 4 5 6 7 8 9 10 // 10 9 8 7 6 5 4 3 2 1 resize
// change the size of the list #include <iostream> #include <list> int main () { list<int> l(10); cout << "Size of list l = " << l.size(); l.resize(100); cout << "After l.resize(100)" << endl; cout << "Size of list l = " << l.size(); l.resize(5); cout << "After l.resize(5)" << endl; cout << "Size of list l = " << l.size(); return 0; } OUTPUT: // Size of list l = 10After l.resize(100) // Size of list l = 100After l.resize(5) // Size of list l = 5 reverse
// reverse the list #include <iostream> #include <list> #include <algorithm> #include <numeric> using namespace std; int main () { list<int> l(10); iota(l.begin(),l.end(),1); copy(l.begin(),l.end(), ostream_iterator<int>(cout," ")); cout << endl; l.reverse(); copy(l.begin(),l.end(), ostream_iterator<int>(cout," ")); cout << endl; return 0; } OUTPUT: // 1 2 3 4 5 6 7 8 9 10 // 10 9 8 7 6 5 4 3 2 1 size
// the number the elements in the list #include <iostream> #include <list> #include <algorithm> int main () { list<int> l(5,0); copy(l.begin(),l.end(), ostream_iterator<int>(cout," ")); cout << endl; cout << "Size of list = " << l.size() << endl; int size = l.size(); for ( int i=0; i<size; i++ ) // or while ( !l.empty() ) - safer { l.pop_front(); cout << "Size of list = " << l.size() << endl; } return 0; } OUTPUT: // 0 0 0 0 0 // Size of list = 5 // Size of list = 4 // Size of list = 3 // Size of list = 2 // Size of list = 1 // Size of list = 0 sort 1.
// sorts the list #include <iostream> #include <list> #include <algorithm> #include <functional> using namespace std; template <class T> class Print { public: void operator () (T& t) cout << t << " "; } }; //----------------------------- int main () { int ary[] = {3,2,5,7,3,6,7,2,4,5}; list<int> li(ary,ary+10); Print<int> print; cout << "Before sorting\nli : "; for_each(li.begin(),li.end(),print); cout << endl << endl; li.sort(greater<int>()); cout << "After li.sort(greater())\nli : "; for_each(li.begin(),li.end(),print); cout << endl << endl; li.sort(less<int>()); cout << "After li.sort(less())\nli : "; for_each(li.begin(),li.end(),print); cout << endl; return 0; } OUTPUT: // Before sorting // li : 3 2 5 7 3 6 7 2 4 5 // // After li.sort(greater<int>()) // li : 7 7 6 5 5 4 3 3 2 2 // // After li.sort(less<int>()) // li : 2 2 3 3 4 5 5 6 7 7 sort 2.
// sorts with user datatype #include <iostream> #include <iomanip> #include <list> #include <string> using namespace std; template <class T> class Member { public: Member(T f, T l) : first_n(f), last_n(l) {} void print(); private: string last_n, first_n; // for sort() list member function friend bool operator < (Member& m1, Member& m2) { return m1.last_n < m2.last_n; } }; //--------------------------------------- template <class T> void Member<T>::print() { cout.setf(ios::left); cout << setw(15) << last_n.c_str() << first_n << endl; } typedef Member<string> M; //======================================== int main () { list<M> li; li.push_back(M("Linda","Smith")); li.push_back(M("Frost","Robert")); li.push_back(M("Alex","Amstrong")); cout << "Before sorting by last name:\n" << "============================" << endl; list<M>::iterator It = li.begin(); while ( It != li.end() ) { (It++)->print(); } cout << endl; li.sort(); cout << "After sorting by last name:\n" << "============================" << endl; It = li.begin(); while ( It != li.end() ) { (It++)->print(); } return 0; } OUTPUT: // Before sorting by last name: // ============================ // Smith Linda // Robert Frost // Amstrong Alex // // After sorting by last name: // ============================ // Amstrong Alex // Robert Frost // Smith Linda splice
// merge two lists #include <iostream> #include <list> #include <algorithm> #include <iterator> using namespace std; template <class T> class Print { public: void operator () (T& t) { cout << t << " "; } }; //==================================== int main () { ist<int> li1, li2, li3, li4; Print print; for ( int i=0; i<5; i++ ) { li1.push_back(i); li2.push_back(i+5); li3.push_back(i+10); li4.push_back(i+15); } cout << "li1 : "; for_each(li1.begin(),li1.end(),print); cout << endl; cout << "li2 : "; for_each(li2.begin(),li2.end(),print); cout << endl; cout << "li3 : "; for_each(li3.begin(),li3.end(),print); cout << endl; cout << "li4 : "; for_each(li4.begin(),li4.end(),print); cout << endl << endl; li1.splice(li1.end(),li2); cout << "li1 : "; for_each(li1.begin(),li1.end(),print); cout << endl << endl; li1.splice(li1.end(),li3,li3.begin(),li3.end()); cout << "li1 : "; for_each(li1.begin(),li1.end(),print); cout << endl << endl; list<int>::iterator It; It = find(li4.begin(),li4.end(),18); li1.splice(li1.begin(),li4,It); cout << "li1 : "; for_each(li1.begin(),li1.end(),print); cout << endl; cout << "li4 : "; for_each(li4.begin(),li4.end(),print); cout << endl; return 0; } OUTPUT: // li1 : 0 1 2 3 4 // li2 : 5 6 7 8 9 // li3 : 10 11 12 13 14 // li4 : 15 16 17 18 19 // // li1 : 0 1 2 3 4 5 6 7 8 9 // // li1 : 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 // // li1 : 18 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 // li4 : 15 16 17 19 swap
// exchange two lists #include <iostream> #include <list> #include <algorithm> #include <numeric> using namespace std; void print (list<int>& l) { list<int>::iterator It = l.begin(); while ( It != l.end() ) { cout << *(It++) << " "; } cout << endl; } //=============================== int main () { list<int> li1(5), li2(5); iota(li1.begin(),li1.end(),1); iota(li2.begin(),li2.end(),5); cout << "li1 : "; print(li1); cout << "li2 : "; print(li2); li1.swap(li2); cout << endl <<"After swapping:" << endl; cout << "li1 : "; print(li1); cout << "li2 : "; print(li2); return 0; } OUTPUT: // li1 : 1 2 3 4 5 // li2 : 5 6 7 8 9 // // After swapping: // li1 : 5 6 7 8 9 // li2 : 1 2 3 4 5 unique
// removes duplicate elements #include <iostream> #include <list> #include <algorithm> #include <iomanip> #include <string> using namespace std; template <class T> class Member { public: Member(T f, T l) : first_n(f), last_n(l) {} void print(); private: string last_n, first_n; // for sort function friend bool operator < (Member& m1, Member& m2) { return m1.last_n < m2.last_n; } // for merge and unique functions friend bool operator == (Member& m1, Member& m2) { return m1.last_n == m2.last_n; } }; //--------------------------------------- template <class T> void Member<T>::print() { cout.setf(ios::left); cout << setw(15) << last_n.c_str() << first_n << endl; } typedef Member<string> M; //======================================== int main () { list<M> li1; li1.push_back(M("Linda","Smith")); li1.push_back(M("Robert","Frost")); li1.push_back(M("Alex","Amstrong")); list li2; li2.push_back(M("Linda","Smith")); li2.push_back(M("John","Wood")); li2.push_back(M("Alex","Amstrong")); li1.sort(); li2.sort(); li1.merge(li2); cout << "li1 after sorting and mergin" << endl; list<M>::iterator It = li1.begin(); while ( It != li1.end() ) { (It++)->print(); } cout << endl; li1.unique(); cout << "After li1.unique()" << endl; It = li1.begin(); while ( It != li1.end() ) { (It++)->print(); } cout << endl; return 0; } OUTPUT: // li1 after sorting and mergin // Amstrong Alex // Amstrong Alex // Frost Robert // Smith Linda // Smith Linda // Wood John // // After li1.unique() // Amstrong Alex // Frost Robert // Smith Linda // Wood John