#include <bits/stdc++.h>
using namespace std;
 
#pragma region Macros
#define Faster ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define ll long long
#define ld long double
#define pii pair<int, int>
#define pll pair<long long, long long>
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define pb push_back
#define ff first
#define ss second
#define endl '\n'
#define yes cout << "YES" << endl
#define no cout << "NO" << endl
#define m1 cout << -1 << endl
#pragma endregion
 
#pragma region Math
const ll MOD = 1e9 + 7;
ll gcd(ll a, ll b) { return __gcd(a, b); }
ll lcm(ll a, ll b) { return (a / gcd(a, b)) * b; }
#pragma endregion
 
void solve() {
    int n;  cin>>n;
    string s;   cin>>s;
    int ans=n-1, cnt=0;
 
    for(int i=2;i<n;i++){
        if(i%2==0){
            if(s[i]==s[i-2])
                ans--;
        }
        else{
            if(s[i]==s[i-2])
                ans--;
        }
    }
    cout<<ans<<endl;
}
 
int main() {
    Faster;
    int t = 1;
    cin >> t;
    while (t--) solve();
    return 0;
}

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

Nwo2CmFhYWJjYwoxMAphYWFhYWFhYWFhCjYKYWJjZGVmCjcKYWJhY2FiYQo2CmNjY2ZmZgo0CmFiYmEKNQphYmFiYQo=

7
6
aaabcc
10
aaaaaaaaaa
6
abcdef
7
abacaba
6
cccfff
4
abba
5
ababa