# 1858. Digits Fun!

You enjoy working with numbers that contain only square digits (namely, 0, 1, 4 and 9). The sequence containing only these digits is 0, 1, 4, 9, 10, 11, 14… output the N-th term (indexed from 0) in this sequence.

### 输入格式

There are several test cases,each test case contain only a integer N(0<=N<=2^31-1).

### 输出格式

output the N-th term (indexed from 0) in this sequence.

### 样例

Input
16
123

Output
100
1949


73 人解决，117 人已尝试。

93 份提交通过，共有 353 份提交。

4.4 EMB 奖励。