Tweaked some more, still not correct?

Question about the task

Under discussion

I am sure this is becoming waaaay more complicated than it should be. I have tweaked it again, as I found a few cases that didn't work. Now I still can't pass it, but I have no clue where to look for next?

The input is a mathematical expression in the form of a String.
The expression may include whole numbers, fractional numbers, parentheses (), spaces, negative signs -, exponents ^, sin(x), cos(x), and tan(x)
For sin(x), cos(x), and tan(x), the expression inside the parentheses should be interpreted as degrees. For example: cos (3 + 19 * 3) = 0.5
An exponent is expressed as follows: a^(1+3) would be a^4, which is equivalent to a*a*a*a.
Using recursion, evaluate the expression and calculate the number of mathematical operations. Display the result separated by spaces.
Display results that are accurate to the hundredths place, e.g. for 0.33333, display 0.33. Use the standard rules for rounding.
A negative sign before a number is also considered a mathematical operation.
Don't create additional fields in the Solution class.
Don't use indirect recursion.

Example that uses the sin, *, -, +, *, and + operations:
sin(2*(-5+1.5*4)+28)

Result:
0.5 6

Example that uses the tan and ^ operations:
tan(2025 ^ 0.5)

Result:
1 2

Requirements:

Additional fields must not be created in the Solution class.
The recurse method must display the result of evaluating the passed expression (examples are in the task conditions).
The recurse method must not be static.
The recurse method must be recursive.

package com.codegym.task.task34.task3404; import javax.script.ScriptEngine; import javax.script.ScriptEngineManager; import javax.script.ScriptException; import java.text.DecimalFormat; import java.text.NumberFormat; import java.util.ArrayList; import java.util.Arrays; import java.util.List; /* Recursion for mathematical expressions */ public class Solution { public static void main(String[] args) { Solution solution = new Solution();// solution.recurse( "3-1+5", 0); solution.recurse("sin(2*(-5+1.5*4)+28)", 0); // Expected output: 0.5 6 solution.recurse("tan(2025 ^ 0.5)", 0); // Expected output: 1 2 solution.recurse("1+2.41+1", 0); // Expected 4.41 2 solution.recurse("2^2", 0); // Expected 4 1 solution.recurse(" 3 + 4 * 2 / ( 1 - 5 ) ^ 2 ^ 3", 0); //Expected 3 6 } public void recurse(final String expression, int countOperation) { //implement String currentExpression = expression; if (countOperation == 0) { countOperation = getOperationsCount(expression); } if (isNumber(currentExpression)) { NumberFormat numberFormat = new DecimalFormat("#.##"); Double result = Double.parseDouble(currentExpression); System.out.println(String.format("%s %d", numberFormat.format(result), countOperation)); return; } else if (currentExpression.contains("(")) { int lastParenthStart = currentExpression.lastIndexOf("("); int lastParenthEnd = currentExpression.indexOf(")", lastParenthStart); String mostInnerExpr = currentExpression.substring(lastParenthStart + 1, lastParenthEnd); String innerFunction = lastParenthStart > 2 ? expression.substring(lastParenthStart - 3, lastParenthStart) : "nop"; if (isNumber(mostInnerExpr)) { double mostInnerResult = Double.parseDouble(mostInnerExpr); switch (innerFunction) { case "sin": mostInnerResult = Math.sin(mostInnerResult * Math.PI / 180); lastParenthStart -= 3; break; case "cos": mostInnerResult = Math.cos(mostInnerResult * Math.PI / 180); lastParenthStart -= 3; break; case "tan": mostInnerResult = Math.tan(mostInnerResult * Math.PI / 180); lastParenthStart -= 3; break; } currentExpression = currentExpression.substring(0, lastParenthStart) .concat(String.valueOf(mostInnerResult)) .concat(currentExpression.substring(lastParenthEnd + 1)); } else { // Expression in innermost block if (innerFunction.equalsIgnoreCase("sin") || innerFunction.equalsIgnoreCase("cos") || innerFunction.equalsIgnoreCase("tan")) { currentExpression = currentExpression.substring(0, lastParenthStart + 1) .concat(String.valueOf(calcExpression(mostInnerExpr))) .concat(currentExpression.substring(lastParenthEnd)); } else { currentExpression = currentExpression.substring(0, lastParenthStart) .concat(String.valueOf(calcExpression(mostInnerExpr))) .concat(currentExpression.substring(lastParenthEnd + 1)); } } } else { currentExpression = String.valueOf(calcExpression(currentExpression)); } recurse(currentExpression, countOperation); } private double calcExpression(String expression) { String sum = expression.replaceAll(" ", ""); while (sum.contains("^") || sum.contains("*") || sum.contains("/") || sum.contains("+") || sum.contains("-") && !sum.startsWith("-")) { if (sum.contains("^")) { int index = sum.indexOf("^"); double[] aIndex = findA(sum, index); double[] bIndex = findB(sum, index); double answer = Math.pow(aIndex[0], bIndex[0]); sum = sum.substring(0, (int) aIndex[1]) + answer + sum.substring((int) bIndex[1]); } else if (sum.contains("*")) { int index = sum.indexOf("*"); double[] aIndex = findA(sum, index); double[] bIndex = findB(sum, index); double answer = aIndex[0] * bIndex[0]; sum = sum.substring(0, (int) aIndex[1]) + answer + sum.substring((int) bIndex[1]); } else if (sum.contains("/")) { int index = sum.indexOf("/"); double[] aIndex = findA(sum, index); double[] bIndex = findB(sum, index); double answer = aIndex[0] / bIndex[0]; sum = sum.substring(0, (int) aIndex[1]) + answer + sum.substring((int) bIndex[1]); }else if (sum.contains("+") && sum.contains("-") && sum.indexOf("-") > 0) { boolean posFirst = sum.indexOf("+") < sum.indexOf("-"); if (posFirst) { int index = sum.indexOf("+"); double[] aIndex = findA(sum, index); double[] bIndex = findB(sum, index); double answer = aIndex[0] + bIndex[0]; sum = sum.substring(0, (int) aIndex[1]) + answer + sum.substring((int) bIndex[1]); }else { int index = sum.indexOf("-"); double[] aIndex = findA(sum, index); double[] bIndex = findB(sum, index); double answer = aIndex[0] - bIndex[0]; sum = sum.substring(0, (int) aIndex[1]) + answer + sum.substring((int) bIndex[1]); } }else if (sum.contains("+")) { int index = sum.indexOf("+"); double[] aIndex = findA(sum, index); double[] bIndex = findB(sum, index); double answer = aIndex[0] + bIndex[0]; sum = sum.substring(0, (int) aIndex[1]) + answer + sum.substring((int) bIndex[1]); } else if (sum.contains("-")) { int index = sum.indexOf("-"); double[] aIndex = findA(sum, index); double[] bIndex = findB(sum, index); double answer = aIndex[0] - bIndex[0]; sum = sum.substring(0, (int) aIndex[1]) + answer + sum.substring((int) bIndex[1]); } } return Double.parseDouble(sum); } private double[] findA(String sum, int index){ StringBuilder stringBuilder = new StringBuilder(); double[] a = new double[2]; for (int i = index-1; i >= 0; i--){ if (sum.charAt(i) == '^' || sum.charAt(i) == '*' || sum.charAt(i) == '/' || sum.charAt(i) == '+'){ a[1] = i+1; break; } if (sum.charAt(i) == '-' && i != 0 && sum.charAt(i-1) != '^' && sum.charAt(i-1) != '*' && sum.charAt(i-1) != '/' && sum.charAt(i-1) != '+' && sum.charAt(i-1) != '-'){ a[1] = i+1; break; } stringBuilder.insert(0, sum.charAt(i)); if (i == 0){ a[1] = i; } } try{ a[0] = Double.parseDouble(stringBuilder.toString()); }catch (Exception e){ int x = Integer.parseInt(stringBuilder.toString()); a[0] = x * 1.0; } return a; } private double[] findB(String sum, int index){ StringBuilder stringBuilder = new StringBuilder(); double[] b = new double[2]; for (int i = index+1; i < sum.length(); i++){ if (sum.charAt(i) == '^' || sum.charAt(i) == '*' || sum.charAt(i) == '/' || sum.charAt(i) == '+' || sum.charAt(i) == '-' && i != index+1){ b[1] = i; break; } stringBuilder.append(sum.charAt(i)); if (i == sum.length()-1){ b[1] = i+1; } } try{ b[0] = Double.parseDouble(stringBuilder.toString()); }catch (Exception e){ int x = Integer.parseInt(stringBuilder.toString()); b[0] = x * 1.0; } return b; } private boolean isNumber(String expression) { if (expression == null) return false; return expression.matches("^[+-]?\\d+(\\.\\d+)?"); } public Solution() { //don't delete } private int getOperationsCount(String expression) { String[] operations = new String[] {"sin", "cos", "tan", "\\^", "\\+", "\\-", "\\*", "\\/"}; int operationsCount = 0; for (String operation : operations) { operationsCount += expression.split(operation).length - 1; } char prev = '.'; for (char x : expression.toCharArray()){ if (x == prev){ if (x == '-'){ operationsCount--; } } prev = x; } return operationsCount; } }

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