+ 1

Why does an array index start from zero..

answer me in simple sentence

30th Mar 2018, 2:40 PM
Suhail Ahmad
Suhail Ahmad - avatar
3 odpowiedzi
+ 5
If you're standing in place, are you in a place? Yes. Have you moved in any direction yet? No. So you're in position 0 when standing in place. When you take a step forward, you've moved 1 step, so your index from your original starting point is 1. If you take another step, you're now 2 steps away from your original point, which is a total of 3 points. If you go back 2 steps from there, you're back at your original point, so you're back at 0 in reference to your starting point.
30th Mar 2018, 2:51 PM
Fata1 Err0r
Fata1 Err0r - avatar
+ 3
The reason is in mathematics: A variable storing an array, in reality doesn't store the array itself, but the memory address of the array. Each item of the array need S space of memory to be stored. First item of the array is stored at the same memory address M of the array itself. Second item is stored to M+S Third item is stored to M+2*S... Nth item is stored to M+(N-1)*S... So, with indexes starting from zero, the formula to get the memory address of the <index> item is simply: M + <index>*S
30th Mar 2018, 3:01 PM
visph
visph - avatar
+ 1
Because array refers to the memory location of its elements which starts with zero. The index of the array is an offset.
30th Mar 2018, 3:47 PM
Jeevitra Sree
Jeevitra Sree - avatar