Why it doesnt output 9 outputs?

Question

class Program
{
static void Main(string[] args)
{

int[] b = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };

for (int k = 1; k <= b.Length; k++)
{
b[k] = k*k;
Console.WriteLine(b[k]);
}

}
}

Answer 1

I think it's because you have to change the limits in the loop. First index in the array is 0, so k = 0. The last index in the loop is b.Length - 1 so k = b.Length - 1.

Answer 2

simply change b[k] into b[k-1] and it will work.

b[k-1]=k*k;
Console.WriteLine(b[k-1]);

Answer 3

D⚽⚽⚽⚽7⃣7⃣7⃣ yeah, agree.
the problem is b[k] =k*k because in last iteration k will be 9 and b[9] will show an error. There's 8 indices (indexes).

Answer 4

The indices are 9, because in the array start counting at 0, so when we reach 8 => we have 9 elements. The problem is the last calculation because the last element is b[8], not b[9] => out of array bounds.