The answer
It relates to memory addressing. The index represents the memory offset from the starting position of the array. The first element has an offset of 0.
Common Off-By-One Errors in For Loops
Why do arrays start at index 0?
More FAQs in Common Off-By-One Errors in For Loops
It is a logical bug where a loop boundary is miscalculated, causing the loop to execute one time too many or one time too few.
Always ensure your loop condition uses strictly less than (<) the array's length, rather than less than or equal to (<=).
Your code will run without crashing, but it will skip the final element, resulting in an incorrect output or a failed test case.
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