; lab8.asm - a function that checks if an array is a premutation of the other
;
        .MODEL SMALL
        .STACK 100h
        .DATA

            Count DB 10 DUP(0)

        .CODE
            PUBLIC _PermutationArray
            _PermutationArray PROC NEAR
                PUSH BP
                MOV BP,SP
                PUSH DI
                PUSH SI

                XOR CX,CX                       ; CX = 0

                MOV DI,[BP+4]                   ; DI = int array1[]
                MOV SI,[BP+6]                   ; SI = int array2[]
                MOV CX,[BP+8]                   ; CX = int size
                DEC CX                          ; i--

                CounterLoop:
                    CMP CX,0                    ; i >= 0
                    JL ExitCounterLoop          ; i < 0
                    ADD Count[DI],1             ; count[array1[i]]++
                    SUB Count[SI],1             ; count[array2[i]]--
                    INC DI
                    INC SI
                    DEC CX                      ; i--
                    JMP CheckLoop

                ExitCounterLoop:
                MOV DI,[BP+8]                   ; CX = int size
                DEC CX                          ; i--

                CheckLoop:
                    CMP CX,0                    ; size >= i
                    JL ReturnTrue               ; return 1
                    CMP Count[DI],0             ; if(count[i])
                    JG ReturnFalse              ; return 0
                    DEC CX                      ; i--
                    JMP CheckLoop

                ReturnTrue:
                MOV AX,1
                JMP Exit

                ReturnFalse:
                XOR AX,AX

                Exit:
                POP SI
                POP DI
                POP BP
                RET
            _PermutationArray ENDP
        END