Let's determine the memory addresses occupied by each instruction starting at address 1000:
Address 1000 (size 4): MOV R1, (5000)→R1=MEMORY[5000]=10
Address 1004 (size 4): MOV R2, (R3)→R2=MEMORY[R3]
Address 1008 (size 2): ADD R2, R1→R2=R1+R2
Address 1010 (size 4): MOV (R3), R2→MEMORY[R3]=R2
Address 1014 (size 2): INC R3→R3=R3+1
Address 1016 (size 2): DEC R1→R1=R1−1
Address 1018 (size 2): BNZ 1004 → branches back to address 1004 if R1=0
Address 1020 (size 1): HALT
Tracing the loop iterations:
Initially, R1=10, R3=3000.
Iteration 1: MEMORY[3000] is updated to 50+10=60; R3 becomes 3001, R1 becomes 9.
Iteration 2: MEMORY[3001] is updated to 50+9=59; R3 becomes 3002, R1 becomes 8.
Iteration 10: MEMORY[3009] is updated to 50+1=51; R3 becomes 3010, R1 becomes 0.
When R1=0, the condition BNZ 1004 evaluates to false and the loop terminates. The instruction at memory location 3010 is never updated by the loop, so its content remains unmodified at 50.