I'm allowed to use the C functions printf, scanf, and puts. I get a number from the user (which is easy), but I need to check to see if it's less than 0 or greater than 255? I know how to compare single digit numbers but am stuck on how to compare negative or numbers >9. would cmp eax, 0 and cmp eax,255 work?
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Use scanf to get the input into a number (rather than a text representation of one). From there, just use the appropriate jmp after the comparison instructions. For some, the comparison is signed, for others, not. – enhzflep Oct 26 '14 at 15:43
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The problem is a little bit unclear. Didn't you convert the (ASCII-)input to a register value e.g. with `scanf`? Please add code that shows the problem. – rkhb Oct 26 '14 at 15:44
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It will do what you intend just
whith cmp eax,0 instead of jb you should
use jl (Jump if first operand is Less) cause it will be signed comparison
qwr
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