.section .data
str1:	.fill 50,1,42
str1_len = .-str1
not_alphanum:	.byte 0
.section .text
.global main
main:
	movl $3, %eax
	movl $0, %ebx
	leal str1, %ecx
	movl $str1_len, %edx
	int $0x80

	movl %eax, %esi #esi sadrzi duzinu stringa
	leal str1, %eax #adresa stringa u %eax
	decl %eax
	decl %esi
proveri:
	incl %eax
	cmpb $'\n', (%eax)
	je ispis

	cmpb $'0', (%eax)
	jb zameni

	cmpb $'9', (%eax)
	jbe proveri

	cmpb $'A', (%eax)
	jb zameni

	cmpb $'Z', (%eax)
	jbe proveri

	cmpb $'a', (%eax)
	jb zameni

	cmpb $'z', (%eax)
	jbe proveri

zameni:
	incb not_alphanum
	movb $'0', (%eax)
	jmp proveri
ispis:
	movl $4, %eax
	movl $1, %ebx
	leal str1, %ecx
	movl %esi, %edx
	int $0x80
kraj:
	movl $1, %eax
	movb not_alphanum, %bl
	int $0x80