algol report

8/13/2019 Algol Report

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ALGOL

ALGOL 58, ALGOL 60 and

ALGOL 68


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HISTORY

ALGOL was developed jointly by a committee of European and Amcomputer scientists in a meeting in 1958 at Zurich

ALGOL (ALGOrithmic Language)

First formalized in a report titled ALGOL 58

Progressed through reports named ALGOL 60

ALGOL 68. It was designed by an international committee to be a unlanguage.


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ALGOL 58


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HISTORY ALGOL 58

Released in December 1958 with great reception.

Americans look at it as a collection of languages instead of an universal lan

Inspired three majordesigns:

MAD-Michigan Algorithmic DecoderNELIAC-Navy Electronics Laboratory International ALGOL Compiler

JOVIAL-Jules Own Version International Programming Algorithmic Lan Used by U.S Air Force by Jules I.Schwart.


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Three different syntaxes

reference syntax publication syntax implementation syntax.


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Design Process

Syntax should be as close as possible to standard scientific notation. Readable. Easy to learn and easy to understand. Simplicity for periodical publications describing the computing proc Programs should be mechanically translatable into machine language


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3 Complication of Algol 58

developing new compilers

training new personnel

motivate people to a new language


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ALGOL 60


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ALGOL 60

ALGOL 60 (short for ALGO rithmic Language 1960 ) is a member of the ALGOLof computer programming languages. It gave rise to many other programming languages, including:

BCPL B PASCAL Simula C

ALGOL 60 was the first language implementing nested function definitions with lscope.


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ALGOL 60 Reserved words and restricted identifiers

There are 35 such reserved words in the standard Burroughs large systems sub-lan

ALPHA

ARRAY

BEGIN

BOOLEANCOMMENT

CONTINUE

DIRECT`

DO

DOUBLE

ELSE

ENDEVENT

FALSE

FILE

FOR

FORMAT

GO

IFINTEGER

LABEL

LIST

LONG

OWN

POINTER

PROCEDUREREAL

STEP

SWITCH

TASK

THEN

TRUE

UNTIL VALUE

WHILE

ZIP


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There are 71 such restricted identifiers instandard Burroughs large systems sub-lang

ACCEPT

AND

ATTACH

BY

CALL

CASE

CAUSE

CLOSE

DEALLOCATE

DEFINE

DETACH

DISABLE

DISPLAY

DIV

DUMP

ENABLE

EQL

EQV

EXCHANGE

EXTERNAL

FILL

FORWARD

GEQ

GTR

IMP

IN

INTERRUPT

IS

LB

LEQ

LIBERATE

LINE

LOCK

LSS

MERGE

MOD

MONITOR

MUX

NEQ

NO

NOT

ON

OPEN

OR

OUT

PICTURE

PROCESS

PROCURE

PROGRAMDUMP

RB

READ

RELEASE

REPLACE

RESET

RESIZE

REWIND

RUN

SCAN

SEEK

SET

SKIP

SORT

SPACE

SWAP

THRU

TIMES

TO

WAIT

WHEN

WITH

WRITE


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ALGOL SAMPLE CODE

BEGIN

FILE F (KIND=REMOTE);

EBCDIC ARRAY E[0:11];

REPLACE E BY HELLO WORLD !; WRITE(F, *, E);

END .


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A SIMPLIER PROGRAM USING INLIN

FORMAT:BEGIN

FILE F (KIND=REMOTE);

WRITE(F, );

END.


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SIMPLIER PROGRAM USING THE

DISPLAY STATEMENTBEGIN DISPLAY(HELLO WORLD!) END.


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Is an imperative computer programminglanguage that was conceived as a successor tothe ALGOL 60 programming language, design

with the goal of a much wider scope of applicand more rigorously defined syntax and seman


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Its features include expression-based syntaxuser-declared types and structures/tagged-unioreference model of variables and referenceparameters, string, array and matrix slicing, anconcurrency.

was designed by IFIP Working Group 2.1


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In 1970, ALGOL 68R became the first working compiler for ALGOL 68 .

In the 1973 revision, certain features - suchas proceduring, gommas and formalbounds - were omitted .


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Operating Systems written in ALGOL 6

Cambridge CAP computer Eldon 3

Flex machine VME


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Program representation

Representation language - used to describe algorithms in p work

Strict language - rigorously defined in the Report Reference language - intended to be used in actual compile

input.

int a real int = 3 ;


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Stropping regimes - methods to denote identifiers


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The basic datatypes (called modes in Algol 68

parlance) are :>Real>Int>compl (complex number)

>Bool>Char>bits and bytes.


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Primitive-declarer:

bits - a "packed vector" of bool. bytes - a "packed vector" of char.

string - a flexible array of char. Sema - a semaphore which can be initialised w

the operator level.


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Example:

int max=99;

mode newtype = [0:9][0:max] struct ( lreal a, b, c, short int i, j, k, ref real r );


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THANK YOU!RAINNALYN CAPARAS

KRISTINE DIANNE TECSON

MARINEL NOCONHERMOGENES AMORES

ADRIAN AMOR PEREYRA

algol report

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