#include <bits/stdc++.h>   using namespace std;   void printv(vector<long long int> v) {     long long int sz = v.size();     for (long long int i = 0; i < sz; i++) {       if (i == sz - 1)         cout << v[i] <<   n ;       else         cout << v[i] <<    ;     }   }   void input(long long int a[], long long int sz) {     for (long long int i = 0; i < sz; i++) cin >> a[i];   }   void print(long long int a[], long long int sz) {     for (long long int i = 0; i < sz; i++) {       if (i == sz - 1)         cout << a[i] <<   n ;       else         cout << a[i] <<    ;     }   }   long long int dx1[] = {1, 1, 0, -1, -1, -1, 0, 1};   long long int dy1[] = {0, 1, 1, 1, 0, -1, -1, -1};   long long int dx2[] = {1, 0, -1, 0};   long long int dy2[] = {0, 1, 0, -1};   long long int mul(long long int a, long long int b,                     long long int p = 1000000007) {     return ((a % p) * (b % p)) % p;   }   long long int add(long long int a, long long int b,                     long long int p = 1000000007) {     return (a % p + b % p) % p;   }   long long int power(long long int x, long long int y,                       long long int p = 1000000007) {     long long int res = 1;     x = x % p;     while (y > 0) {       if (y & 1) res = (res * x) % p;       y = y >> 1;       x = (x * x) % p;     }     return res;   }   long long int modInverse(long long int n, long long int p = 1000000007) {     return power(n, p - 2, p);   }   long long int ncrMod(long long int n, long long int r,                        long long int p = 1000000007) {     if (r == 0) return 1;     long long int fac[n + 1];     fac[0] = 1;     for (long long int i = 1; i <= n; i++) fac[i] = fac[i - 1] * i % p;     return (fac[n] * modInverse(fac[r], p) % p * modInverse(fac[n - r], p) % p) %            p;   }   bool ispeed2ime(long long int n) {     for (int i = 2; i * i <= n; i++) {       if (n % i == 0) {         return false;       }     }     return true;   }   bool isPowerof2(long long int n) {     while (n > 1) {       if (n % 2 != 0) {         return true;       }       n /= 2;     }     return false;   }   string reverse(string str, int len, int l, int r) {     if (l < 0 || r >= len || l > r) return str;     while (l < r) {       char c = str[l];       str[l] = str[r];       str[r] = c;       l++;       r--;     }     return str;   }   void solve() {     long long int n;     cin >> n;     string s;     cin >> s;     string temp =   ;     long long int maxi1 = 0, maxi2 = 0;     for (int i = 0; i < n - 1; i++) {       temp += s[i];       temp += s[i + 1];       if (temp ==  10 ) {         maxi1++;       } else if (temp ==  01 ) {         maxi2++;       }       temp =   ;     }     long long int maxi = max(maxi1, maxi2);     long long int cnt = n / 2 - (maxi);     cout << cnt <<   n ;   }   int main() {     ios_base::sync_with_stdio(0);     cin.tie(NULL);     cout.tie(NULL);     long long int t = 1;     cin >> t;     while (t--) {       solve();     }     return 0;   }   