.386
.model flat, stdcall
.data
source BYTE "This is the source string", 0
target BYTE SIZEOF source DUP('#')
.code

start:
    ;write your code here
    mov  esi, 0
    mov  ecx, SIZEOF source

    Ciclo:
	mov  al, source[ecx]
	mov  target[esi], al
	inc  esi
    loop Ciclo

	mov al,source[ecx]
	mov target[esi], al
    ret
    END start