program
    class Main <empty>
        static func main inttype
            formals
            stmtblock
                vardef i inttype
                vardef a inttype
                vardef b inttype
                vardef c inttype
                assign
                    varref a
                    intconst 0
                assign
                    varref b
                    intconst 1
                assign
                    varref c
                    intconst 2
                switch
                    add
                        varref a
                        varref b
                switch
                    varref i
                    default:
                    assign
                        varref c
                        intconst 3
                switch
                    varref c
                    case:
                        intconst 0
                        break
                repeat
                    les
                        varref a
                        varref b
                repeat
                    gtr
                        varref a
                        varref b
                    stmtblock
                repeat
                    equ
                        varref a
                        varref b
                    assign
                        varref c
                        add
                            varref a
                            varref b
                    assign
                        varref b
                        varref a
                repeat
                    equ
                        varref a
                        varref b
                    stmtblock
                        assign
                            varref c
                            add
                                varref a
                                varref b
                        assign
                            varref b
                            varref a
                return
                    intconst 0