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# Doubt on Arrays

sanyasirao nali
Greenhorn
Posts: 6
Why arrays are started with 0(zero) index...?

example: a[5]={23,5,34,23,21}
here a[0]=23,a[1]=5 . . . . . . ,a[4]=21.
here a[] started with a[0] not a[1]......why arrays are starting with 0(zero) index...?

dennis deems
Ranch Hand
Posts: 808
An array is not merely a logical structure; it is a contiguous chunk of memory space. What makes using arrays so blindingly fast is that we can get any array element by applying an offset ( the index number ) to the start of the array. To get the first array element, we go to the start of the array and apply an offset of zero. To get the fifth element we go to the start of the array and apply an offset of four.

Tony Docherty
Bartender
Posts: 2941
59
Why arrays are started with 0(zero) index...?

Arrays in Java start at 0 but not all languages take this approach.
See this thread for an explanation: http://www.coderanch.com/t/384946/java/java/starting-index-array