#include<bits/stdc++.h>
#define ll long long
using namespace std;
int x,y;
int i,j,p; 
char ab[100001],bc[100001];
int a[10001],b[10001];
int jw;
int maxn,maxj;
int main( ){
	cin>>p;
	cin>>ab>>bc;
	x=strlen(ab);
	y=strlen(bc);
	for(i=0;i<x;i++)
		a[i]=ab[x-i-1]-'0';
	for(i=0;i<y;i++)
		b[i]=bc[y-i-1]-'0';
	maxn=max(x,y);
	for(i=0;i<maxn;i++){
		a[i]=a[i]+b[i]+jw;
		jw=a[i]/p;
		a[i]%=p;
	}
	if(jw==1) cout<<jw;
	for(i=maxn-1;i>=0;i--){
		if (a[i]<10) cout<<a[i];
        else cout<<(char)(a[i]+'A'-10);
	}
	return 0;
}