Stress tests and verdicts

Questions 1 to 5 of 8

1. 1. The checker prints seed 3: MISMATCH brute=5 solution=1 on the input 4 2 / 2 4 3 5. What is the best next step?

   Submit the fast solution, since a single mismatch can be a flukeShrink the input, keeping each change only while the two outputs still differ, then read the line that handles the boundaryRaise the checker's timeout to 10 secondsDelete the brute force and compare the fast solution with the sample only
2. 2. Which events make the checker stop and print the failing input?

   Pick every answer that is true.

   The brute force and the solution print different answersThe solution exits with a non-zero codeThe solution does not finish within the 2-second timeoutThe solution prints a trailing space, which split() does not ignore
3. 3. After 3000 random small inputs all matched, an AI says the fast solution is now proven correct. Which reply is right?

   Correct, because 3000 random cases cover every possible inputNot proven: it shows only that the two programs agreed on the small inputs tried, so bugs that need large values, such as overflow, can still hideCorrect, because the brute force was tested and cannot be wrongNot proven, but it is proven correct for every input under 10^9
4. 4. A program prints the correct answer and then exits with code 1. What verdict does this site give?

   PassedWrong answerRuntime errorTime limit exceeded
5. 5. A naive solution is run as timeout 5 ./naive < big.txt; echo exit=$?. It prints exit=124 and no answer. What does this mean?

   timeout stopped the program after 5 seconds, so the run went over the limitThe program read the wrong input fileThe program ran out of memoryThe output was correct, and 124 is the number of answers