P1800D

#include <bits/stdc++.h>
using namespace std;
#define ll long long
void solve()
{
    ll n;
    cin>>n;
    string s;
    cin>>s;
    ll k = n-1;
    for (ll i=0; i<n-2; i++){
        if (s[i]==s[i+2]) k--;
    }
    cout<<k<<"\n";
}
int main()
{
    int t;
    cin>>t;
    while(t--){
        solve();
    }
}