How do you check if two arrays are equal element-wise?

• A. Compare the first element only and assume the rest are equal
• B. Compare the arrays by memory address equality
• C. Use a library function to compare entire arrays
• D. Compare each element in a loop and return false if any mismatch

Answer: (D)

To determine if two arrays are equal element-wise, you must verify that they have the same length and that every corresponding pair of elements is identical. Start by checking the lengths; if they differ, they can’t be equal. If the lengths match, walk through each index from 0 to length-1 and compare the two elements at that position. If any pair differs, you can conclude they’re not equal and stop early. If you finish the loop with no mismatches, the arrays are equal.

This approach is definitive because it directly tests every element in corresponding positions. Relying on memory addresses only tells you whether both references point to the same array object, not whether their contents match. Checking just the first element misses mismatches that could appear later. While a library function that compares whole arrays can be convenient in some languages, the explicit element-by-element check makes the concept clear and ensures correctness in any context.