This challenge uses the famous KMP algorithm. It isn't really important to understand how KMP works, but you should understand what it calculates.

A KMP algorithm takes a string, $\mbox{S}$, of length $N$ as input. Let's assume that the characters in $\mbox{S}$ are indexed from $\mbox{1}$ to $N$; for every prefix of $\mbox{S}$, the algorithm calculates the length of its longest valid border in linear complexity. In other words, for every $\boldsymbol{i}$ (where $1\leq i\leq N$) it calculates the largest $\boldsymbol{l}$ (where $0\leq l\leq i-1$) such that for every $\boldsymbol{p}$ (where $1\leq p\leq l$) there is $S[p]=S[i-l+p]$.

Here is an implementation example of KMP:

kmp[1] = 0;
for (i = 2; i <= N; i = i + 1){
l = kmp[i - 1];
while (l > 0 && S[i] != S[l + 1]){
l = kmp[l];
}
if (S[i] == S[l + 1]){
kmp[i] = l + 1;
}
else{
kmp[i] = 0;
}
}

Given a sequence $x_1,x_2,\ldots,x_{26}$, construct a string, $\mbox{S}$, that meets the following conditions:

The frequency of letter '$\boldsymbol{a}$' in $\mbox{S}$ is exactly $x_1$, the frequency of letter '$\boldsymbol{b}$' in $\mbox{S}$ is exactly $x_2$, and so on.
Let's assume characters of $\mbox{S}$ are numbered from $\mbox{1}$ to $N$, where $\sum\limits_{i=1}^{n}x_{i}=N$. We apply the KMP algorithm to $\mbox{S}$ and get a table, $kmp$, of size $N$. You must ensure that the sum of $kmp[i]$ for all $\boldsymbol{i}$ is minimal.

If there are multiple strings which fulfill the above conditions, print the lexicographically smallest one.

Input Format

A single line containing $26$ space-separated integers describing sequence $\boldsymbol{x}$.

Constraints

The sum of all $x_i$ will be a positive integer $\leq10^{6}$.

Output Format

Print a single string denoting $\mbox{S}$.

Sample Input
2 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Sample Output
aabb

Explanation

The output string must have two '$\boldsymbol{a}$' and two '$\boldsymbol{b}$'. There are several such strings but we must ensure that sum of $kmp[i]$ for all $1<=i<=4$ is minimal. See the figure below:

The minimum sum is $\mbox{1}$. Among all the strings that satisfy both the condition, "aabb" is the lexicographically smallest.

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