#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
template<class T> void check_min(T &a, const T &b){ a = (a < b) ? a : b; }
template<class T> void check_max(T &a, const T &b){ a = (a > b) ? a : b; }
#define all(x) (x).begin(), (x).end()

int main(){
    ios::sync_with_stdio(false);
    cin.tie(NULL);

    int t;
    cin >> t;

    while(t--){
        int n;
        cin >> n;

        string s, t;
        cin >> s >> t;

        for(int i = 0; i < n; ++i)
            s[i] = ((s[i] - '0') ^ (t[i] - '0')) + '0';

        vector<int> v;
        int curr = 0;
        for(int i = 0; i < n; ++i){
            if(s[i] == '0'){
                if(curr)
                    v.push_back(curr);
                curr = 0;
            }
            else{
                ++curr;
            }
        }
        if(curr)
            v.push_back(curr);

        if(v.size() > 2)
            cout << "0\n";
        else{
            if(v.size() == 0){
                ll ans = (ll)n * (ll)(n + 1) / 2;
                cout << ans << "\n";
            }
            else if(v.size() == 1){
                cout << (v[0] - 1) * 2 << "\n";
            }
            else{
                cout << 6 << "\n";
            }
        }
    }
}