#include <cstring>

#include <algorithm>

#include <cstdio>

#include <cstdlib>

#include <cmath>

#include <vector>

using namespace std;

const int N=100000+5;

int n,Next[N],same[N],fa[N];

vector <int> diff[N],d2[N];

char s[N];

int getf(int k){

	return fa[k]==k?k:fa[k]=getf(fa[k]);

}

int main(){

	scanf("%d",&n);

	for (int i=1;i<=n;i++){

		fa[i]=i;

		diff[i].clear();

		d2[i].clear();

	}

	for (int i=1,x;i<=n;i++){

		scanf("%d",&x);

		Next[i]=i-x;

		if (i==1)

			continue;

		int k;

		for (k=i-1;k>0;k=Next[k])

			if (Next[k]+1==Next[i])

				break;

			else

				diff[i].push_back(Next[k]+1),diff[Next[k]+1].push_back(i);

		if (Next[i]>0){

			same[i]=Next[k]+1;

			fa[getf(i)]=getf(Next[k]+1);

		}

		else

			same[i]=-1;

	}

	for (int i=1;i<=n;i++){

		int f=getf(i);

		for (int j=0;j<diff[i].size();j++)

			d2[f].push_back(diff[i][j]);

	}

	s[1]='a';

	for (int i=2;i<=n;i++){

		if (same[i]!=-1){

			s[i]=s[same[i]];

			continue;

		}

		bool f[26];

		memset(f,0,sizeof f);

		int bh=getf(i);

		for (int j=0;j<d2[bh].size();j++){

			if (d2[bh][j]>=i)

				continue;

			f[s[d2[bh][j]]-'a']=1;

		}

		int j;

		for (j=0;j<26;j++)

			if (!f[j])

				break;

		s[i]=j+'a';

	}

	for (int i=1;i<=n;i++)

		printf("%c",s[i]);

	return 0;

}