Question
Make it a multiple of 3
You're given a positive integer N, containing digits from 1 to 9. Let k be the number of digits in N. You want to make a multiple of 3 by erasing at least 0 and at most k−1 digits from N and concatenating the remaining digits without changing the order. Determine whether it is possible to make a multiple of 3 in this way. If it is possible, find the minimum number of digits that must be erased to make such a number, print -1 otherwise.
Input
The input consists of a single integer N.

Constraints
1≤N≤10^18

None of the digits in N is 0.
Output
If it is impossible to make a multiple of 3, print -1; otherwise, print the minimum number of digits that must be erased to make such a number.
Example
Sample Input 1
35
Sample Output 1
1

Sample Input 2
369
Sample Output 2
0

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