Answer:
Step-by-step explanation:
a) Let's analyze the stack for each IJVM instruction:
ILOAD j: Loads the value of variable j onto the stack.
Stack: [j]
ILOAD n: Loads the value of variable n onto the stack.
Stack: [j, n]
ISUB: Subtracts the top two values on the stack (n - j).
Stack: [n - j]
BIPUSH 21: Pushes the constant value 21 onto the stack.
Stack: [n - j, 21]
IADD: Adds the top two values on the stack ((n - j) + 21).
Stack: [n - j + 21]
DUP: Duplicates the top value on the stack.
Stack: [n - j + 21, n - j + 21]
IADD: Adds the top two values on the stack ((n - j + 21) + (n - j + 21)).
Stack: [2 * (n - j) + 42]
ISTORE į: Stores the top value on the stack into variable į.
Stack: []
b) IJVM code with comments:
ILOAD j // Load value of variable j onto the stack
ILOAD n // Load value of variable n onto the stack
ISUB // Subtract n - j
BIPUSH 21 // Push constant value 21 onto the stack
IADD // Add (n - j) + 21
DUP // Duplicate the top value on the stack
IADD // Add top two values on the stack (2 * (n - j) + 42)
ISTORE į // Store the top value on the stack into variable į
c) The equivalent Java code for the provided IJVM code:
int result = 2 * (n - j) + 42;
į = result;
Note: In the Java code, the variables j, n, and į should be declared and assigned appropriate values before executing the code.