4th Open Serbian Optimizing Puzzle Championship

[majkll]

I have a question about puzzle #1. I think the fourth digit of y1 may not be zero since it is most significant digit (although it is also least significant digit for a single digit number).

4th digit in y1 can not be zero - it is most significant, and it is also first digit in that one-digit-number.

Thanks for nice set of puzzles

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