I need my MARIE program to output 0 if any number that is inputted is negative or 0, my code is pasted below

INPUT STORE a OUTPUT INPUT STORE b OUTPUT INPUT STORE c OUTPUT

loop1, LOAD cnt ADD a STORE cnt Load b SUBT one STORE b SKIPCOND 400 JUMP loop1

loop2, LOAD d ADD cnt STORE d LOAD c SUBT one STORE c SKIPCOND 400 JUMP loop2 LOAD d OUTPUT HALT

a, DEC 0 b, DEC 0 c, DEC 0 d, DEC 0 one, DEC 1 cnt, DEC 0

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