JuniorTheoryCommon

What does the program print (lines separated by spaces)?

int[] a = [1, 2, 3];
int[] b = a;
b[0] = 10;
b = [7, 8];
Console.WriteLine(a[0]);
Console.WriteLine(b[0]);

10 7

Expecting 1 7: int[] b = a copies the reference, not the array, so b[0] = 10 writes into the array a leads to.
Expecting 7 7: b = [7, 8] puts a new reference into b only, and a still leads to the old array with 10 in it.

JuniorTheoryCommon

int[] a = [1, 2, 3];
int[] b = a;
b[0] = 10;
b = [7, 8];
Console.WriteLine(a[0]);
Console.WriteLine(b[0]);

10 7

Expecting 1 7: int[] b = a copies the reference, not the array, so b[0] = 10 writes into the array a leads to.
Expecting 7 7: b = [7, 8] puts a new reference into b only, and a still leads to the old array with 10 in it.