#include<cstdio>

#define N 200010

int n,m,i,x,r,p,f[N],g[N],fa[N],a[N],v[30];

struct E{int v;E*nxt;}*j,*h[N],pool[N*2],*cur=pool;

inline int min(int a,int b){return a<b?a:b;}

int F(int x){return fa[x]==x?x:fa[x]=F(fa[x]);}

inline void merge(int x,int y){if(x&1)return;fa[F(x>>1)]=F(y>>1);}

inline void add(int x,int y){if(!x||!y||x&1)return;j=cur++;j->v=y>>1;j->nxt=h[x>>=1];h[x]=j;}

inline void read(int&a){char c;while(!(((c=getchar())>='0')&&(c<='9')));a=c-'0';while(((c=getchar())>='0')&&(c<='9'))(a*=10)+=c-'0';}

int main(){

  read(n);m=(n+1)<<1;

  for(i=1;i<=n;i++)read(x),g[i<<1]=x+1,fa[i]=i;

  for(i=1;i<n;i++)read(x),g[i<<1|1]=x+1;

  for(g[m-1]=f[1]=1,i=2;i<m;i++){

    for(f[i]=r>i?min(r-i,f[p*2-i]):1;f[i]<g[i];f[i]++)merge(i-f[i],i+f[i]);

    add(i-f[i],i+f[i]),add(i+f[i],i-f[i]);

    if(i+f[i]>r)r=i+f[i],p=i;

  }

  for(i=1;i<=n;i++)if(!a[F(i)]){

    for(j=h[i];j;j=j->nxt)v[a[F(j->v)]]=i;

    for(x=1;x<=26;x++)if(v[x]<i){a[fa[i]]=x;break;}

  }

  for(i=1;i<=n;i++)putchar('a'+a[fa[i]]-1);

  return 0;

}