lab8.asm

; Denys Mosiuk, IO-92
; KPI 2011

assume cs:code, ds:data, es:data

data segment
DELIMITER   equ ' '

string  db  "A long time ago in a galaxy far far away. "
str_end db '$'
data ends

code segment
beg:
    mov ax, data        ; Init data segments
    mov ds, ax
    mov es, ax

    mov cx, offset str_end - string
    xor dl, dl
    
    cld
    mov al, DELIMITER
    lea di, string
                        
                        ; <Enter> after each 5th
search:                 ; word
    repne scasb         ; Scan for DELIMITER
    jne step
        inc dl          ; If found
        cmp dl, 5       ; And there was 5th
    jne step
        mov byte ptr[di-1], 0ah ; Print nextline
        xor dl, dl      ; and clear counter
step:
    or cx, cx           ; Test for end of line
    jnz search
    
    lea bx, string      ; Print corrected text
    mov ah, 9
    int 21h

    mov ax, 4c00h       ; Exit to DOS
    int 21h
code ends

end beg