#include <bits/stdc++.h>
using namespace std;
void solve() {
  int n;
  cin >> n;
  string s;
  cin >> s;
  int cnt = 0;
  vector<int> v;
  char last = '*';
  for (int i = 0, to = n; i < to; i++) {
    if (last != s[i]) {
      if (cnt > 0) v.push_back(cnt);
      cnt = 1;
      last = s[i];
    } else {
      cnt++;
    }
  }
  v.push_back(cnt);
  int ans = 0;
  int resto = 0;
  for (int i = 0, to = (int)v.size(); i < to; i++) {
    if (v[i] > 1) {
      resto -= (v[i] - 2);
      resto = max(resto, 0);
      ans++;
    } else {
      resto++;
      ans++;
    }
  }
  cout << ans - resto / 2 << '\n';
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(NULL);
  int t = 1;
  cin >> t;
  while (t--) solve();
  return 0;
}
