Three powers
Time Limit: 1 s
Memory Limit: 128 MB
Submission：7
AC：3
Score：99.85
Description
Consider the set of all non-negative integer powers of 3.
Consider the sequence of all subsets of S ordered by the value of the sum of their elements. The question is simple: find the set at the n-th position in the sequence and print it in increasing order of its elements.
Each line of input contains a number n, which is a positive integer with no more than 19 digits. The last line of input contains 0 and it should not be processed.
For each line of input, output a single line displaying the n-th set as described above, in the format used in the sample output.
Samples
input
1
7
14
783
1125900981634049
0
output
{ }
{ 3, 9 }
{ 1, 9, 27 }
{ 3, 9, 27, 6561, 19683 }
{ 59049, 3486784401, 205891132094649, 717897987691852588770249 }