#include <bits/stdc++.h>
using namespace std;
int main()
{int n,p11=0,p00=0,p10=0,p01=0;
long long ans=0;
cin>>n;
string a,b;
cin>>a>>b;
for(int i=0;i<n;i++)
{
    if(a[i]=='1' && b[i]=='1')
        p11++;
    if(a[i]=='0' && b[i]=='0')
        p00++;
    if(a[i]=='1' && b[i]=='0')
        p10++;
    if(a[i]=='0' && b[i]=='1')
        p01++;
}
for(int i=0;i<n;i++)
{
    if(a[i]=='1' && b[i]=='1')
    {
    ans+=p00+p01;
    p11--;
    }
    if(a[i]=='0' && b[i]=='1')
    {
        ans+=p11+p10;
        p01--;
    }
    if(a[i]=='0' && b[i]=='0')
    {
        ans+=p11;
        p00--;
    }
    if(a[i]=='1' && b[i]=='0')
    {
        ans+=p01;
        p10--;
    }
}
cout<<ans;

return 0;
}