Reverse Stringeasy

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

void reverseString(vector<char>& s) {
    // TODO: reverse s in-place using two pointers
}

int main() {
    vector<char> s = {'h', 'e', 'l', 'l', 'o'};
    reverseString(s);
    for (char c : s) cout << c;
    cout << endl; // "olleh"
    return 0;
}