Vector functions in C++
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 clear()  // remove all the elements of the vector container
 insert()  // Inserts new elements before the element at the specified position
 emplace()  // Extends the container by inserting new element at position
 erase()   // Remove elements from a container from the specified position or range
 push_back()  // Push the elements into a vector from the back
 emplace_back() // Constructs an element in-place at the end  
 pop_back()  // Pop or remove elements from a vector from the back   
 resize()  // Changes the number of elements stored     
 swap() // Swap the contents of one vector with another vector of same type. Sizes may differ.