#include<bits/stdc++.h>
using std::cin;using std::cout;using std::cerr;using std::ios;using std::endl;
const int N = 1e5+1000;
int n;
char s[2][N],c[2][N];
int fa[2][N],blk[2][N],wht[2][N];
int Find(int k,int x)
{
    if(x<=0) cerr<<k<<x<<'\n';
    return fa[k][x]==x ? x : fa[k][x]=Find(k,fa[k][x]);
}
void Union(int k,int x,int y)
{
    x=Find(k,x);
    y=Find(k,y);
    if(x==y) return ;
    fa[k][y]=x;
}
void Clear()
{
    memset(s,0,sizeof(s));
    memset(c,0,sizeof(c));
    memset(blk,0,sizeof(blk));
    memset(wht,0,sizeof(wht));
    for(int i=1;i<=n;i++) fa[0][i]=fa[1][i]=i;
}
int main()
{
    ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
    // freopen(".in","r",stdin);
    // freopen(".out","w",stdout);
    freopen("edit.in","r",stdin);
    freopen("edit.out","w",stdout);
    int T; cin>>T;
    while(T--)
    {
        int ans=0;
        cin>>n;
        Clear();
        cin>>(s[0]+1);
        cin>>(s[1]+1);
        cin>>(c[0]+1);
        cin>>(c[1]+1);
        for(int k=0;k<=1;k++)
        {
            for(int i=1;i<=n-1;i++)
            {
                if(c[k][i]=='1' && c[k][i+1]=='1') Union(k,i,i+1);
            }
        }
        for(int k=0;k<=1;k++)
        {
            for(int i=1;i<=n;i++)
            {
                if(c[k][i]=='0') continue;
                if(s[k][i]=='1') blk[k][Find(k,i)]++;
                if(s[k][i]=='0') wht[k][Find(k,i)]++;
            }
        }
        for(int i=1;i<=n;i++)
        {
            if(c[0][i]=='1' && c[1][i]=='1')
            {
                if(blk[0][Find(0,i)]>=1 && blk[1][Find(1,i)]>=1)
                {
                    blk[0][Find(0,i)]--; blk[1][Find(1,i)]--;
                    ans++;
                }
                else if(wht[0][Find(0,i)]>=1 && wht[1][Find(1,i)]>=1)
                {
                    wht[0][Find(0,i)]--; wht[1][Find(1,i)]--;
                    ans++;
                }
            }
            else if(c[0][i]=='0' && c[1][i]=='0')
            {
                if(s[0][i]==s[1][i]) ans++;
            }
            else if(c[0][i]=='0')
            {
                if(s[0][i]=='1' && blk[1][Find(1,i)]>=1) ans++,blk[1][Find(1,i)]--;
                if(s[0][i]=='0' && wht[1][Find(1,i)]>=1) ans++,wht[1][Find(1,i)]--;
            }
            else if(c[1][i]=='0')
            {
                if(s[1][i]=='1' && blk[0][Find(0,i)]>=1) ans++,blk[0][Find(0,i)]--;
                if(s[1][i]=='0' && wht[0][Find(0,i)]>=1) ans++,wht[0][Find(0,i)]--;
            }
        }
        cout<<ans<<'\n';
    }
    return 0;
}