#include <bits/stdc++.h>
using namespace std;
void _print(long long t) { cerr << t; }
void _print(int t) { cerr << t; }
void _print(string t) { cerr << t; }
void _print(char t) { cerr << t; }
void _print(long double t) { cerr << t; }
void _print(double t) { cerr << t; }
void _print(unsigned long long t) { cerr << t; }
template <class T, class V>
void _print(T a[], V sz);
template <class T, class V>
void _print(pair<T, V> p);
template <class T>
void _print(vector<T> v);
template <class T>
void _print(set<T> v);
template <class T, class V>
void _print(map<T, V> v);
template <class T>
void _print(multiset<T> v);
template <class T, class V>
void _print(pair<T, V> p) {
  cerr << "{";
  _print(p.first);
  cerr << " -> ";
  _print(p.second);
  cerr << "}" << endl;
}
template <class T, class V>
void _print(T a[], V sz) {
  for (V i = 0; i < sz; i++) {
    _print(a[i]);
    cerr << " ";
  }
  cerr << endl;
}
template <class T>
void _print(vector<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]" << endl;
}
template <class T>
void _print(set<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]" << endl;
}
template <class T>
void _print(multiset<T> v) {
  cerr << "[ ";
  for (T i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]";
}
template <class T, class V>
void _print(map<T, V> v) {
  cerr << "[ ";
  for (auto i : v) {
    _print(i);
    cerr << " ";
  }
  cerr << "]" << endl;
}
void _printall(long long t) { cout << t; }
void _printall(int t) { cout << t; }
void _printall(string t) { cout << t; }
void _printall(char t) { cout << t; }
void _printall(long double t) { cout << t; }
void _printall(double t) { cout << t; }
void _printall(unsigned long long t) { cout << t; }
template <class T, class V>
void _printall(T a[], V sz);
template <class T, class V>
void _printall(pair<T, V> p);
template <class T>
void _printall(vector<T> v);
template <class T>
void _printall(set<T> v);
template <class T, class V>
void _printall(map<T, V> v);
template <class T>
void _printall(multiset<T> v);
template <class T, class V>
void _printall(T a[], V sz) {
  for (V i = 0; i < sz; i++) {
    _printall(a[i]);
    cout << " ";
  }
  cout << endl;
}
template <class T, class V>
void _printall(pair<T, V> p) {
  _printall(p.ff);
  cout << ",";
  _printall(p.ss);
}
template <class T>
void _printall(vector<T> v) {
  for (T i : v) {
    _printall(i);
    cout << " ";
  }
  cout << endl;
}
template <class T>
void _printall(set<T> v) {
  for (T i : v) {
    _printall(i);
    cout << " ";
  }
  cout << endl;
}
template <class T>
void _printall(multiset<T> v) {
  for (T i : v) {
    _printall(i);
    cout << " ";
  }
  cout << endl;
}
template <class T, class V>
void _printall(map<T, V> v) {
  for (auto i : v) {
    _printall(i);
    cout << " ";
  }
  cout << endl;
}
long long MAXN = 200001;
long long spf[200001];
void sieve() {
  spf[1] = 1;
  for (int i = 2; i < MAXN; i++) {
    spf[i] = i;
  }
  for (long long i = 4; i < MAXN; i += 2) {
    spf[i] = 2;
  }
  for (long long i = 3; i * i < MAXN; i++) {
    if (spf[i] == i) {
      for (long long j = i * i; j < MAXN; j += i) {
        if (spf[j] == j) spf[j] = i;
      }
    }
  }
}
vector<long long> getFactorization(long long x) {
  vector<long long> ret;
  while (x != 1) {
    ret.push_back(spf[x]);
    x = x / spf[x];
  }
  return ret;
}
void solve() {
  long long n;
  cin >> n;
  string s;
  cin >> s;
  vector<int> pre;
  int cnt = 0;
  for (int i = 0; i < n; i++) {
    pre.push_back(1);
  }
  for (int i = n - 2; i >= 0; i--) {
    if (s[i] == s[i + 1]) {
      pre[i] = pre[i + 1] + 1;
    }
  }
  reverse(pre.begin(), pre.end());
  vector<int> fin;
  for (int i = 0; i < pre.size() - 1; i++) {
    if (pre[i] == 1 && pre[i + 1] == 1) {
      fin.push_back(pre[i]);
    } else if (pre[i] >= 1 && pre[i + 1] == 1) {
      fin.push_back(pre[i]);
    }
  }
  if (pre[n - 1] >= 1) {
    fin.push_back(pre[n - 1]);
  }
  int ind1 = fin.size() - 1;
  int ind2 = fin.size() - 1;
  while (pre.size() != 0 && ind1 >= 0 && ind2 >= 0) {
    if (fin[ind1] > 1) {
      cnt++;
      fin.pop_back();
      if (ind2 == ind1) {
        ind2--;
      }
      ind1--;
    } else {
      while (fin[ind2] == 1) {
        ind2--;
      }
      if (ind2 < 0) {
        break;
      } else {
        cnt++;
        fin[ind2]--;
        fin.pop_back();
        ind1--;
      }
    }
  }
  if (pre.size() != 0) {
    cnt += (fin.size() + 1) / 2;
  }
  cout << cnt << endl;
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  long long t = 1;
  cin >> t;
  while (t--) {
    solve();
  }
  cerr << "time taken : " << (float)clock() / CLOCKS_PER_SEC << " secs" << endl;
  return 0;
}
