Sudoku algorithm in C#

Question

I need one liner (or close to it) that verifies that given array of 9 elements doesn\'t contain repeating numbers 1,2,3,...,9. Repeating zeroes do not count (they represent empt

Answer 1

This is about 50-250 times faster than a LINQ solution (depending on how early the duplicate is found):

public static bool IsValid(int[] values) {
    int flag = 0;
    foreach (int value in values) {
        if (value != 0) {
            int bit = 1 << value;
            if ((flag & bit) != 0) return false;
            flag |= bit;
        }
    }
    return true;
}