Edge Cases Checklist

Use this before submitting coding answers.

Arrays

• n = 0, if allowed
• n = 1
• all elements same
• negative numbers
• duplicates
• already sorted
• reverse sorted
• very large values

Strings

• empty string, if allowed
• single character
• spaces
• uppercase/lowercase
• repeated characters
• punctuation
• palindrome with odd length
• palindrome with even length

Number problems

• n = 0
• n = 1
• negative input
• large input
• prime check for 2
• factorial overflow
• reverse number ending with zero

Pair/sum problems

• no valid pair
• duplicate pair
• pair using same element not allowed
• negative values

Common submission checks

• Did you include required headers/imports?
• Did you read all input?
• Did you print only required output?
• Did you avoid extra debug prints?
• Did you reset variables for each test case?
• Did you handle integer overflow if needed?