C++ output elements of a vector not expected

Question

I'm practicing vector and ranged for loop, my code:

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

int main(){
    int size,element;
    cout<<"enter vector size: ";
    cin>>size;
    vector<int>v(size);
    for(int i=0; i<size; i++){
        cout<<i<<"\t";
        cin>>element;
        v.push_back(element);
    }
    for(int p : v) cout<<p<<" ";
}

I entered 3 then 1, 2, 3 but the output is "0 0 0 1 2 3". Could you please explain me where the 0s are from? Thank you very much!

Answer 1

vector<int>v(size);

This creates a vector of having size equal to size variable. Now if you do push_back it will create a new vector and with size+1 and add the element to it. Instead inside for loop do cin>>v[i];