#include<bits/stdc++.h>
using namespace std;
#define mod 1000000007
#define ll long long int
#define endl “\n”
#define pb push_back
#define mp make_pair
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
int t;
cin >> t;
while(t–)
{
ll n,ans=0,i,k=0,kh=1,l;
string r,s;
cin>>s;
cin>>r;
n=s.length();
vectorv,v1;// vector v contains the indices where s[i]!=r[i]
// vector v1 contains the difference of adjacent element of vevtor v.
for(i=0;i<n;i++){
if(s[i]!=r[i]){
v.push_back(i);
k++;
}}
ll n1=v.size();
if(k==1)
cout<<“1”<<endl;
else{
l=k;
ans=kl;
//cout<<n1;
for(i=0;i<n1-1;i++){
v1.pb(v[i+1]-v[i]-1);
}
for(i=0;i<v1.size();i++){
ans=min(ans,(k-1)(l+v1[i]));
k–;
l=l+v1[i];
}
cout<<ans<<endl;}
}
return 0;
}