Count the number of zeros (using a dynamic array)

#include <iostream>
using namespace std;
int main()
{
    int m, counter=0;
    cout << "How many numbers will you check: "<<endl;
    cin >> m;
    int* U;
    U = new int[m];
    for (int i = 0; i < m; i++) {
        cout << "Enter an element: "<<endl;
        cin >> U[m];
        if (U[m] == 0) {
            counter++;
        }
    }
    cout << "The number of 0-s in this array is: "<<counter;
}