#include <bits/stdc++.h>
#pragma GCC optimize(2)
using namespace std;
const int inf = 0x3f3f3f3f;
const long long INF = 0x3f3f3f3f3f3f3f3fLL;
const double PI = acos(-1.0);
const long double eps = 1e-8;
const int mod = 1e9 + 7;
const int maxn = 2e5 + 100;
const int N = 3e5 + 100;
const int M = 500 + 10;
const long long mm = (1LL << 32);
template <class T>
inline void read(T &x) {
  x = 0;
  char c = getchar();
  bool f = 0;
  for (; !isdigit(c); c = getchar()) f ^= c == '-';
  for (; isdigit(c); c = getchar()) x = x * 10 + (c ^ 48);
  x = f ? -x : x;
}
template <class T>
inline void write(T x) {
  if (x < 0) {
    putchar('-');
    x = -x;
  }
  T y = 1;
  int len = 1;
  for (; y <= x / 10; y *= 10) ++len;
  for (; len; --len, x %= y, y /= 10) putchar(x / y + 48);
}
long long qpow(long long a, long long b, long long mod) {
  long long ans = 1;
  while (b) {
    if (b & 1) ans = (ans * a) % mod;
    b >>= 1;
    a = (a * a) % mod;
  }
  return ans;
}
int a[N];
char s[N];
int tot;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int T;
  cin >> T;
  while (T--) {
    int n;
    cin >> n;
    cin >> (s + 1);
    if (n == 1) {
      cout << 1 << "\n";
      continue;
    }
    tot = 0;
    int pre = 1;
    for (int i = 2; i <= n; ++i) {
      if (s[i] != s[i - 1]) {
        a[++tot] = i - pre;
        pre = i;
      }
    }
    if (s[n] = s[n - 1]) a[++tot] = n - pre + 1;
    int ans = 0;
    int l = 1, r = 1;
    while (l <= tot) {
      while (r < l) r++;
      if (a[l] > 1)
        ans++, l++;
      else {
        while (r <= tot && a[r] == 1) ++r;
        if (r <= tot) {
          a[r]--;
          l++;
          ans++;
        } else
          l += 2, ans++;
      }
    }
    cout << ans << "\n";
  }
  return 0;
}
