.386
.model flat

.code
_toUnsigned proc
	mov ecx, [esp + 4]

	mov eax, 0
_while:
	cmp	byte ptr[ecx], 0
	je _end
	mov edx, 10
	mul edx
	mov bl, byte ptr[ecx]
	sub bl, '0'
	movsx esi, bl
	add eax, esi
	inc ecx
	jmp _while
_end:
	ret
_toUnsigned endp
end