diff --git a/MathCalculator.js b/MathCalculator.js
new file mode 100644
index 0000000..29be312
--- /dev/null
+++ b/MathCalculator.js
@@ -0,0 +1,107 @@
+// MathCalculator.ts
+// tsc MathCalculator.ts -t esnext
+export class MathCalculator {
+    static processFormulaVerbose(line) {
+        try {
+            const result = MathCalculator.processFormulaString(line);
+            console.log(`The result of '${line}' is '${result}'`);
+        }
+        catch (error) {
+            console.error(`Error: ${error.message}`);
+        }
+    }
+    static processFormulaString(line) {
+        const words = line.split(" ");
+        return MathCalculator.processFormulaWords(words, 0, words.length - 1);
+    }
+    static processFormulaWords(words, startIndex, endIndex) {
+        if (endIndex < startIndex)
+            throw new RangeError("Invalid index: endIndex < startIndex");
+        let currentOperator = null;
+        let result = null;
+        for (let currentIndex = startIndex; currentIndex <= endIndex; currentIndex++) {
+            const word = words[currentIndex];
+            const isNumber = !isNaN(parseFloat(word));
+            if (isNumber || word === "(") {
+                let number;
+                if (word === "(") {
+                    let depth = 0;
+                    let closingIndex = -1;
+                    for (let searchClosingIndex = currentIndex; searchClosingIndex <= endIndex; searchClosingIndex++) {
+                        if (words[searchClosingIndex] === "(")
+                            depth++;
+                        else if (words[searchClosingIndex] === ")")
+                            depth--;
+                        if (words[searchClosingIndex] === ")" && depth === 0) {
+                            closingIndex = searchClosingIndex;
+                            break;
+                        }
+                    }
+                    if (closingIndex === -1) {
+                        throw new Error("Invalid input: no closing parenthesis");
+                    }
+                    number = MathCalculator.processFormulaWords(words, currentIndex + 1, closingIndex - 1);
+                    currentIndex = closingIndex;
+                }
+                else {
+                    number = parseFloat(word);
+                }
+                if (currentOperator === null) {
+                    if (result !== null) {
+                        throw new Error("Invalid input: operator expected");
+                    }
+                    result = number;
+                }
+                else if (currentOperator === "sqrt") {
+                    result = Math.sqrt(number);
+                }
+                else if (result !== null) {
+                    switch (currentOperator) {
+                        case "+":
+                            result += number;
+                            break;
+                        case "-":
+                            result -= number;
+                            break;
+                        case "*":
+                            result *= number;
+                            break;
+                        case "/":
+                            if (number === 0)
+                                throw new Error("Division by zero");
+                            result /= number;
+                            break;
+                        case "^":
+                            result = Math.pow(result, number);
+                            break;
+                        case "%":
+                            result %= number;
+                            break;
+                        case "sqrt":
+                            result = Math.sqrt(number);
+                            break;
+                        default:
+                            throw new Error(`Invalid operator: '${currentOperator}'`);
+                    }
+                }
+                else {
+                    throw new Error("Invalid input: no result available");
+                }
+                currentOperator = null;
+            }
+            else if (["+", "-", "*", "/", "^", "%", "sqrt"].includes(word)) {
+                if (currentOperator !== null) {
+                    throw new Error(`Invalid input: operator '${currentOperator}' already set`);
+                }
+                currentOperator = word;
+            }
+            else {
+                throw new Error(`Invalid input: '${word}' is not a number or operator`);
+            }
+        }
+        if (result === null) {
+            throw new Error("Invalid input: no result computed");
+        }
+        return result;
+    }
+}
diff --git a/MathCalculator.ts b/MathCalculator.ts
new file mode 100644
index 0000000..4499419
--- /dev/null
+++ b/MathCalculator.ts
@@ -0,0 +1,112 @@
+// MathCalculator.ts
+// tsc MathCalculator.ts -t esnext
+
+export class MathCalculator {
+
+    static processFormulaVerbose(line: string): void {
+        try {
+            const result = MathCalculator.processFormulaString(line);
+            console.log(`The result of '${line}' is '${result}'`);
+        } catch (error) {
+            console.error(`Error: ${error.message}`);
+        }
+    }
+
+    static processFormulaString(line: string): number {
+        const words = line.split(" ");
+        return MathCalculator.processFormulaWords(words, 0, words.length - 1);
+    }
+
+    static processFormulaWords(words: string[], startIndex: number, endIndex: number): number {
+        if (endIndex < startIndex) throw new RangeError("Invalid index: endIndex < startIndex");
+
+        let currentOperator: string | null = null;
+        let result: number | null = null;
+
+        for (let currentIndex = startIndex; currentIndex <= endIndex; currentIndex++) {
+            const word = words[currentIndex];
+            const isNumber = !isNaN(parseFloat(word));
+
+            if (isNumber || word === "(") {
+                let number: number;
+
+                if (word === "(") {
+                    let depth = 0;
+                    let closingIndex = -1;
+
+                    for (let searchClosingIndex = currentIndex; searchClosingIndex <= endIndex; searchClosingIndex++) {
+                        if (words[searchClosingIndex] === "(") depth++;
+                        else if (words[searchClosingIndex] === ")") depth--;
+
+                        if (words[searchClosingIndex] === ")" && depth === 0) {
+                            closingIndex = searchClosingIndex;
+                            break;
+                        }
+                    }
+
+                    if (closingIndex === -1) {
+                        throw new Error("Invalid input: no closing parenthesis");
+                    }
+
+                    number = MathCalculator.processFormulaWords(words, currentIndex + 1, closingIndex - 1);
+                    currentIndex = closingIndex;
+                } else {
+                    number = parseFloat(word);
+                }
+
+                if (currentOperator === null) {
+                    if (result !== null) {
+                        throw new Error("Invalid input: operator expected");
+                    }
+                    result = number;
+                } else if (currentOperator === "sqrt") {
+                    result = Math.sqrt(number);
+                } else if (result !== null) {
+                    switch (currentOperator) {
+                        case "+":
+                            result += number;
+                            break;
+                        case "-":
+                            result -= number;
+                            break;
+                        case "*":
+                            result *= number;
+                            break;
+                        case "/":
+                            if (number === 0) throw new Error("Division by zero");
+                            result /= number;
+                            break;
+                        case "^":
+                            result = Math.pow(result, number);
+                            break;
+                        case "%":
+                            result %= number;
+                            break;
+                        case "sqrt":
+                            result = Math.sqrt(number);
+                            break;
+                        default:
+                            throw new Error(`Invalid operator: '${currentOperator}'`);
+                    }
+                } else {
+                    throw new Error("Invalid input: no result available");
+                }
+
+                currentOperator = null;
+            } else if (["+", "-", "*", "/", "^", "%", "sqrt"].includes(word)) {
+                if (currentOperator !== null) {
+                    throw new Error(`Invalid input: operator '${currentOperator}' already set`);
+                }
+                currentOperator = word;
+            } else {
+                throw new Error(`Invalid input: '${word}' is not a number or operator`);
+            }
+        }
+
+        if (result === null) {
+            throw new Error("Invalid input: no result computed");
+        }
+
+        return result;
+    }
+}
diff --git a/index.html b/index.html
new file mode 100644
index 0000000..b286023
--- /dev/null
+++ b/index.html
@@ -0,0 +1,34 @@
+<!DOCTYPE html>
+<html lang="en">
+
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>math formula calculator</title>
+</head>
+
+<body>
+
+    <h1>Math Formula Calculator</h1>
+    <input type="text" id="formula" placeholder="Enter formula">
+    <button id="calculate">Calculate</button>
+    <p id="result"></p>
+
+    <script type="module">
+
+        //import { evaluate } from 'mathjs'
+
+        // tsc MathCalculator.ts -t esnext
+        import { MathCalculator } from './MathCalculator.js'
+
+        function calculate() {
+            var formula = document.getElementById('formula').value;
+            var result = MathCalculator.processFormulaString(formula);
+            document.getElementById('result').innerText = result;
+        }
+
+        document.getElementById('calculate').addEventListener('click', calculate);
+    </script>
+</body>
+
+</html>
\ No newline at end of file