cin >> s >> t;

if(s.size() < t.size()){

reverse(s.begin(), s.end());

ll d = t.size() - s.size();

for(ll i=0;i<d;i++) s.push_back('0');

reverse(s.begin(), s.end());

}

if(s.size() > t.size()){

reverse(t.begin(), t.end());

ll d = s.size() - t.size();

for(ll i=0;i<d;i++) t.push_back('0');

reverse(t.begin(), t.end());

}

ll p1 = s.size() - 1, p2 = t.size() - 1;

ll ans = 0, c = 0;

while(p1 >= 0 && p2 >= 0){

if(s[p1] == '1' && t[p2] == '1'){

c = 0;

p1--;

p2--;

while(p1 >= 0 && p2 >= 0 && (s[p1] == '1' || t[p2] == '1') && !(s[p1] == '1' && t[p2] == '1')) p1-=1, p2-=1, c++;

c++;

ans = max(ans, c);

continue;

}

p1--;

p2--;

}

for(ll i=0;i<t.size();i++)

if(t[i] == '1'){

ans++;

break;

}

cout << ans << "\n";

{

// freopen("input.txt", "r", stdin); //Comment

// freopen("output.txt", "w", stdout); //this out.

ios::sync_with_stdio(false); //Not

cin.tie(NULL); //this.

cout.tie(0); //or this.

ll T;

cin >> T;

while(T--)

solve();

return 0;

}