vector.txt

Using dynamic array in C++ // vectors
push_back ( ) // can be used for taking input.

int main(){   

vector <int> g1; // declaring the array;
vector <int> :: iterator i;  // declaring the iterator
vector <int> :: reverse_iterator ir;   // declaring the reverse iterator

1. begin() – Returns an iterator pointing to the first element in the vector

2. end() – Returns an iterator pointing to the theoretical element that follows last element in the vector

3. rbegin() – Returns a reverse iterator pointing to the last element in the vector (reverse beginning). It moves from last to first element

4. rend() – Returns a reverse iterator pointing to the theoretical element preceding the first element in the vector (considered as reverse end)

for (int i = 1; i <= 5; i++)    
g1.push_back(i);    // pushing the input inside the array

cout << "Output of begin and end\t:\t"; 
for (i = g1.begin(); i != g1.end(); ++i) 
cout << *i << '\t';  

OUTPUT- 1 2 3 4 5

cout << "Output of rbegin and rend\t:\t"; 
for (ir = g1.rbegin(); ir != g1.rend(); ++ir)        
cout << '\t' << *ir;  

output 5 4 3 2 1
return 0;
}
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