#include <bits/stdc++.h>
using namespace std;
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int t, n;
  string s;
  cin >> t;
  while (t--) {
    cin >> n >> s;
    vector<int> szs;
    char prev = s.front();
    int sz = 0;
    for (char c : s) {
      if (c != prev) {
        szs.push_back(sz);
        sz = 1;
      } else
        sz++;
      prev = c;
    }
    szs.push_back(sz);
    int cnt = 0, id = 1;
    for (int i : szs) {
      if (i > 1) cnt += min(i - 1, id - cnt);
      id++;
    }
    cout << cnt + (szs.size() - cnt + 1) / 2 << "\n";
  }
  return 0;
}
