84 lines
1.8 KiB
JavaScript
84 lines
1.8 KiB
JavaScript
const display = document.querySelector("#display");
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let previousNumber = 0;
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let lastOperation = "";
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function doOperation(operation, numA, numB) {
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numA = Number(numA);
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numB = Number(numB);
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switch (operation) {
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case "+":
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return numA + numB;
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break;
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}
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}
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//Set numbers logic
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const numbers = document.querySelectorAll(".number");
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numbers.forEach((number) => {
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number.addEventListener("click", (event) => {
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updateDisplay(event.target.innerText);
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});
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});
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function updateDisplay(number) {
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let currentResult = display.value;
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if (currentResult === "0") {
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display.value = number;
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} else {
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display.value += number;
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}
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}
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function reset() {
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display.value = "0";
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previousNumber = "0";
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lastOperation = "";
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}
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// Set clear button
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const clearButton = document.querySelector(".clear");
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clearButton.addEventListener("click", () => {
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reset();
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});
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// Set backspace button
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backspaceButton = document.querySelector(".backspace");
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backspaceButton.addEventListener("click", () => {
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let result = display.value;
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result = result.slice(0, -1);
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if (result.length === 0) {
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result = "0";
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}
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display.value = result;
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});
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// Operations
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const operators = document.querySelectorAll(".operator");
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operators.forEach((operator) => {
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operator.addEventListener("click", (event) => {
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if (lastOperation) {
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previousNumber = doOperation(
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lastOperation,
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previousNumber,
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display.value,
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);
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} else {
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previousNumber = Number(display.value);
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}
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display.value = "0";
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lastOperation = event.target.innerText;
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});
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});
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// Result button
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const resultButton = document.querySelector(".result");
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resultButton.addEventListener("click", (event) => {
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if (lastOperation) {
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display.value = doOperation(lastOperation, previousNumber, display.value);
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}
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});
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reset();
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