You have two values each of which is either 0 representing "unknown", or one of 1,2,3. Merge them into a single value as follows:
- If both values are nonzero and equal, output that value:
(3,3) -> 3 - If both values are nonzero but unequal, output 0 for unknown:
(1,2) -> 0 - If one value is zero and the other is not, output the nonzero value:
(2,0) -> 2, (0,1) -> 1 - If both values are zero, output zero:
(0,0) -> 0
Test cases:
There are 16 possible input pairs.
| 0 1 2 3
--+--------
0 | 0 1 2 3
1 | 1 1 0 0
2 | 2 0 2 0
3 | 3 0 0 3
(0, 0) -> 0
(0, 1) -> 1
(0, 2) -> 2
(0, 3) -> 3
(1, 0) -> 1
(1, 1) -> 1
(1, 2) -> 0
(1, 3) -> 0
(2, 0) -> 2
(2, 1) -> 0
(2, 2) -> 2
(2, 3) -> 0
(3, 0) -> 3
(3, 1) -> 0
(3, 2) -> 0
(3, 3) -> 3
Leaderboards
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