#include<bits/stdc++.h>
using namespace std;

const int N=1000005;

int T,n,a[N];

int read(){
	int f=1,k=0;
	char c=getchar();
	while(c<'0'||c>'9'){
		if(c=='-')f=-1;
		c=getchar();
	}
	while(c>='0'&&c<='9'){
		k=k*10+c-'0';
		c=getchar();
	}
	return f*k;
}

void sol(){
	int num=0,lx[3],rx[3];
	bool runn=0;
	for(int i(1);i<=n;++i)
		if(a[i]){
			if(runn)rx[num]=i;
			else{
				if(num==2){
					puts("0");
					return;
				}
				lx[++num]=i;rx[num]=i;
				runn=1;
			}
		}
		else runn=0;
	if(num==0){
		printf("%lld\n",(n+1ll)*n/2);
		return;
	}
	if(num==1){
		//cout<<'\n'<<"qk1 "<<lx[1]<<" "<<rx[1]<<" "<<n<<'\n';
		printf("%lld\n",(n-1)*2);
		return;
	}
	if(num==2){
		puts("6");
		return;
	}
	return;
}

int main(){
	T=read();
	while(T--){
		n=read();
		for(int i(1);i<=n;++i){
			char ch;scanf(" %c",&ch);
			a[i]=ch-'0';
		}
		for(int i(1);i<=n;++i){
			char ch;scanf(" %c",&ch);
			a[i]^=ch-'0';
		}//cout<<"ans: ";
		sol();
	}
	return 0;
}