feb COOK103B test case

general
1

for the question Chef and Secret Password of COOK103B
I randomly taken two accepted solution just to understand logic then i got that solution 1 and solution 2 has the different output for the following testcase
"

1

9

abdabdabk

"
first program is giving “ab” as output
while second program is giving “a” as output
so at this situation what happens?

2

The correct answer is ab.
The 2nd solution is obviously wrong. Apparently, the test cases are very weak.