Learn Algol - 10 Code Examples & CST Typing Practice Test

ALGOL (Algorithmic Language) is a family of high-level programming languages designed for scientific computations and algorithm description, known for its structured programming features and influence on modern languages like Pascal, C, and Java.

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ALGOL Counter and Theme Toggle ALGOL Fibonacci Sequence ALGOL Factorial Calculator ALGOL Prime Checker ALGOL Sum of Array ALGOL Reverse String ALGOL Multiplication Table ALGOL Temperature Converter ALGOL Simple Alarm Simulation ALGOL Random Walk Simulation

Learn ALGOL with Real Code Examples

Updated Nov 20, 2025

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Code Sample Descriptions

ALGOL Counter and Theme Toggle

begin
    integer count;
    boolean isDark;

    count := 0;
    isDark := false;

    procedure updateUI;
    begin
        print("Counter: ", count);
        print("Theme: ", if isDark then "Dark" else "Light");
    end;

    procedure increment;
    begin
        count := count + 1;
        updateUI;
    end;

    procedure decrement;
    begin
        count := count - 1;
        updateUI;
    end;

    procedure reset;
    begin
        count := 0;
        updateUI;
    end;

    procedure toggleTheme;
    begin
        isDark := not isDark;
        updateUI;
    end;

    comment Simulate actions;
    updateUI;
    increment;
    increment;
    toggleTheme;
    decrement;
    reset;
end

Demonstrates a simple counter with theme toggling using ALGOL-style structured programming.

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ALGOL Fibonacci Sequence

begin
    integer a, b, c, i;
    a := 0;
    b := 1;
    print(a);
    print(b);

    for i := 1 step 1 until 8 do
    begin
        c := a + b;
        print(c);
        a := b;
        b := c;
    end;
end

Generates the first 10 Fibonacci numbers.

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ALGOL Factorial Calculator

begin
    integer n, f, i;
    n := 5;
    f := 1;
    for i := 1 step 1 until n do
    begin
        f := f * i;
    end;
    print(f);
end

Calculates the factorial of a number.

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ALGOL Prime Checker

begin
    integer num, i;
    boolean isPrime;
    num := 13;
    isPrime := true;
    for i := 2 step 1 until num-1 do
    begin
        if num mod i = 0 then
        begin
        isPrime := false;
        goto end_loop;
        end;
    end;
end_loop:
    if isPrime then print("Prime") else print("Not Prime");
end

Checks if a number is prime.

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ALGOL Sum of Array

begin
    integer arr[5], sum, i;
    arr[1] := 1; arr[2] := 2; arr[3] := 3; arr[4] := 4; arr[5] := 5;
    sum := 0;
    for i := 1 step 1 until 5 do
        sum := sum + arr[i];
    print(sum);
end

Calculates the sum of an integer array.

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ALGOL Reverse String

begin
    string s, r;
    integer i;
    s := "Hello";
    r := "";
    for i := length(s) step -1 until 1 do
        r := r + s[i];
    print(r);
end

Reverses a string character by character.

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ALGOL Multiplication Table

begin
    integer n, i;
    n := 5;
    for i := 1 step 1 until 10 do
        print(n, " x ", i, " = ", n*i);
end

Prints multiplication table of a number.

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ALGOL Temperature Converter

begin
    real c, f;
    c := 25.0;
    f := (c * 9.0 / 5.0) + 32.0;
    print(f);
end

Converts Celsius to Fahrenheit.

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ALGOL Simple Alarm Simulation

begin
    integer temperature, threshold;
    temperature := 80;
    threshold := 75;
    if temperature > threshold then
        print("Alarm: Temperature Too High!")
    else
        print("Temperature Normal");
end

Simulates an alarm when a threshold is reached.

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ALGOL Random Walk Simulation

begin
    integer steps, i, position;
    steps := 10;
    position := 0;
    for i := 1 step 1 until steps do
    begin
        if random(2) = 0 then
        position := position + 1
        else
        position := position - 1;
        print(position);
    end;
end

Simulates a 1D random walk using integers.

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Frequently Asked Questions about Algol

What is Algol?

What are the primary use cases for Algol?

Scientific computations. Algorithm description in publications. Academic teaching of programming and algorithms. Mathematical modeling. Compiler research and language design

What are the strengths of Algol?

Introduced modern programming concepts. Structured and readable code. Strong influence on future languages. Well-suited for algorithm description. Formal language definition enables compiler development

What are the limitations of Algol?

Limited hardware and system support. Not widely used for commercial software. Variations between ALGOL 58, 60, and 68 caused portability issues. Lacked extensive standard libraries. Mostly replaced by modern languages in practice

How can I practice Algol typing speed?

CodeSpeedTest offers 10+ real Algol code examples for typing practice. You can measure your WPM, track accuracy, and improve your coding speed with guided exercises.

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Code Sample Descriptions

ALGOL Counter and Theme Toggle

begin
    integer count;
    boolean isDark;

    count := 0;
    isDark := false;

    procedure updateUI;
    begin
        print("Counter: ", count);
        print("Theme: ", if isDark then "Dark" else "Light");
    end;

    procedure increment;
    begin
        count := count + 1;
        updateUI;
    end;

    procedure decrement;
    begin
        count := count - 1;
        updateUI;
    end;

    procedure reset;
    begin
        count := 0;
        updateUI;
    end;

    procedure toggleTheme;
    begin
        isDark := not isDark;
        updateUI;
    end;

    comment Simulate actions;
    updateUI;
    increment;
    increment;
    toggleTheme;
    decrement;
    reset;
end

Demonstrates a simple counter with theme toggling using ALGOL-style structured programming.

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ALGOL Fibonacci Sequence

begin
    integer a, b, c, i;
    a := 0;
    b := 1;
    print(a);
    print(b);

    for i := 1 step 1 until 8 do
    begin
        c := a + b;
        print(c);
        a := b;
        b := c;
    end;
end

Generates the first 10 Fibonacci numbers.

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ALGOL Factorial Calculator

begin
    integer n, f, i;
    n := 5;
    f := 1;
    for i := 1 step 1 until n do
    begin
        f := f * i;
    end;
    print(f);
end

Calculates the factorial of a number.

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ALGOL Prime Checker

begin
    integer num, i;
    boolean isPrime;
    num := 13;
    isPrime := true;
    for i := 2 step 1 until num-1 do
    begin
        if num mod i = 0 then
        begin
        isPrime := false;
        goto end_loop;
        end;
    end;
end_loop:
    if isPrime then print("Prime") else print("Not Prime");
end

Checks if a number is prime.

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ALGOL Sum of Array

begin
    integer arr[5], sum, i;
    arr[1] := 1; arr[2] := 2; arr[3] := 3; arr[4] := 4; arr[5] := 5;
    sum := 0;
    for i := 1 step 1 until 5 do
        sum := sum + arr[i];
    print(sum);
end

Calculates the sum of an integer array.

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ALGOL Reverse String

begin
    string s, r;
    integer i;
    s := "Hello";
    r := "";
    for i := length(s) step -1 until 1 do
        r := r + s[i];
    print(r);
end

Reverses a string character by character.

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ALGOL Multiplication Table

begin
    integer n, i;
    n := 5;
    for i := 1 step 1 until 10 do
        print(n, " x ", i, " = ", n*i);
end

Prints multiplication table of a number.

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ALGOL Temperature Converter

begin
    real c, f;
    c := 25.0;
    f := (c * 9.0 / 5.0) + 32.0;
    print(f);
end

Converts Celsius to Fahrenheit.

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ALGOL Simple Alarm Simulation

begin
    integer temperature, threshold;
    temperature := 80;
    threshold := 75;
    if temperature > threshold then
        print("Alarm: Temperature Too High!")
    else
        print("Temperature Normal");
end

Simulates an alarm when a threshold is reached.

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ALGOL Random Walk Simulation

begin
    integer steps, i, position;
    steps := 10;
    position := 0;
    for i := 1 step 1 until steps do
    begin
        if random(2) = 0 then
        position := position + 1
        else
        position := position - 1;
        print(position);
    end;
end

Simulates a 1D random walk using integers.

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Frequently Asked Questions about Algol

What is Algol?

What are the primary use cases for Algol?

Scientific computations. Algorithm description in publications. Academic teaching of programming and algorithms. Mathematical modeling. Compiler research and language design

What are the strengths of Algol?

What are the limitations of Algol?

How can I practice Algol typing speed?

CodeSpeedTest offers 10+ real Algol code examples for typing practice. You can measure your WPM, track accuracy, and improve your coding speed with guided exercises.