#include<iostream>

 #include<cstdio>

 #include<cstdlib>

 #include<cstring>

 #include<algorithm>

 #include<cmath>

 #include<queue>

 #include<complex>

 #define ll long long

 #define N 500020

 using namespace std;

 int read(){

   int x=,f=;char ch=getchar();

   while(ch<''||ch>''){if(ch=='-')f=-;ch=getchar();}

   while(ch>=''&&ch<=''){x=x*+ch-'';ch=getchar();}

   return x*f;

 }

 struct CD{

   double a,b;

   CD(double x=,double y=){a=x;b=y;}

   friend CD operator +(CD n1,CD n2){return CD(n1.a+n2.a,n1.b+n2.b);}

   friend CD operator -(CD n1,CD n2){return CD(n1.a-n2.a,n1.b-n2.b);}

   friend CD operator *(CD n1,CD n2){return CD(n1.a*n2.a-n1.b*n2.b,n1.a*n2.b+n1.b*n2.a);}

 };

 int n,m,bit=;

 const long double Pi=acos(-1.0);

 void FFT(CD *a,int n,int type){

   for(int i=,j=;i<n;i++) {

     if(j>i)swap(a[i],a[j]);

     int k=n;

     while(j&(k >>= ))j&=~k;

     j|=k;

   }

   for(int i=;i<=bit;i++){

     CD w_n(cos(*type*Pi/(<<i)),sin(*type*Pi/(<<i)));

     for(int j=;j<(<<bit);j+=(<<i)){

       CD w(,);

       for(int k=j;k<j+(<<(i-));k++){

          CD tmp=a[k],tt=w*a[k+(<<(i-))];

          a[k]=a[k]+tt;

          a[k+(<<(i-))]=tmp-tt;

          w=w*w_n;

       }

     }

   }

   if(type<) for(int i=;i<(<<bit);i++) a[i].a=(a[i].a+0.5)/(<<bit);

 }

 CD poly1[N],poly2[N];

 int c[N*];

 char ch[N];

 int main (){

   n=read();

   scanf("%s",ch+);

   for(int i=;i<n;i++)poly1[i]=(double)(ch[n-i]-'');

   scanf("%s",ch+);

   for(int i=;i<n;i++)poly2[i]=(double)(ch[n-i]-'');

   bit=;

   while(<<bit<(n<<))bit++;

   n=<<bit;

   FFT(poly1,n,);FFT(poly2,n,);

   for(int i=;i<n;i++)poly1[i]=poly1[i]*poly2[i];

   FFT(poly1,n,-);

   int jin=,top=;

   for(int i=;i<n;i++){

     jin+=(int)(poly1[i].a+0.5);

     c[++top]=jin%;

     jin/=;

   }

   while(top&&c[top]==) top--;

   while(top)putchar(c[top--]+'');

   return ;

 }