refactor: Simplify math operations, remove custom precision functions

Co-authored-by: aider (gemini/gemini-2.5-pro) <aider@aider.chat>

calculator/calculator.app.js

@@ -165,57 +165,6 @@ function drawSpecials() {
   drawKeys();
 }
 
-function getIntWithPrecision(x) {
-  var xStr = x.toString();
-  if (xStr.indexOf('e') > -1) {
-    var parts = xStr.split('e');
-    var mantissa = parts[0];
-    var exponent = parseInt(parts[1], 10);
-    var mantissaRadix = mantissa.indexOf('.');
-    var mantissaPrecision = mantissaRadix === -1 ? 0 : mantissa.length - mantissaRadix - 1;
-    return {
-      num: parseInt(mantissa.replace('.', ''), 10),
-      p: mantissaPrecision - exponent
-    };
-  }
-  var xRadix = xStr.indexOf('.');
-  var xPrecision = xRadix === -1 ? 0 : xStr.length - xRadix - 1;
-  return {
-    num: parseInt(xStr.replace('.', ''), 10),
-    p: xPrecision
-  };
-}
-
-function multiply(x, y) {
-  var xNum = getIntWithPrecision(x);
-  var yNum = getIntWithPrecision(y);
-  return xNum.num * yNum.num / Math.pow(10, xNum.p + yNum.p);
-}
-
-function divide(x, y) {
-  var xNum = getIntWithPrecision(x);
-  var yNum = getIntWithPrecision(y);
-  return xNum.num / yNum.num / Math.pow(10, xNum.p - yNum.p);
-}
-
-function sum(x, y) {
-  let xNum = getIntWithPrecision(x);
-  let yNum = getIntWithPrecision(y);
-
-  let diffPrecision = Math.abs(xNum.p - yNum.p);
-  if (diffPrecision > 0) {
-    if (xNum.p > yNum.p) {
-      yNum.num = yNum.num * Math.pow(10, diffPrecision);
-    } else {
-      xNum.num = xNum.num * Math.pow(10, diffPrecision);
-    }
-  }
-  return (xNum.num + yNum.num) / Math.pow(10, Math.max(xNum.p, yNum.p));
-}
-
-function subtract(x, y) {
-  return sum(x, -y);
-}
 
 function toExponential(num, precision) {
   if (num === 0) {
@@ -246,15 +195,17 @@ function fixFloat(n) {
 }
 
 function doMath(x, y, operator) {
+  x = parseFloat(x);
+  y = parseFloat(y);
   switch (operator) {
     case '/':
-      return divide(x, y);
+      return x / y;
     case '*':
-      return multiply(x, y);
+      return x * y;
     case '+':
-      return sum(x, y);
+      return x + y;
     case '-':
-      return subtract(x, y);
+      return x - y;
   }
 }
 
@@ -407,10 +358,11 @@ function buttonPress(val) {
       break;
     case 's':
       if (results != null) {
-        results = multiply(results, results);
+        results = results * results;
         displayOutput(results);
       } else if (currNumber != null) {
-        currNumber = multiply(currNumber, currNumber);
+        var num = parseFloat(currNumber);
+        currNumber = num * num;
         displayOutput(currNumber);
       }
       hasPressedNumber = false;
@@ -520,10 +472,10 @@ function buttonPress(val) {
       break;
     case 'i':
       if (results != null) {
-        results = divide(1, results);
+        results = 1 / results;
         displayOutput(results);
       } else if (currNumber != null) {
-        currNumber = divide(1, currNumber);
+        currNumber = 1 / parseFloat(currNumber);
         displayOutput(currNumber);
       }
       hasPressedNumber = false;