changed error handling

02-Wielomiany/src/META-INF/MANIFEST.MF

@@ -0,0 +1,3 @@
+Manifest-Version: 1.0
+Main-Class: Main
+

02-Wielomiany/src/Main.java

@@ -4,8 +4,7 @@ import java.util.List;
 
 public class Main {
 
-    public static void main(String[] args) throws DivisionErrorException, MultiplierNotFoundException {
+    public static void main(String[] args){
-        //ex input in run console : 2 "1 1 1 0 1" "0 1 1"
         int n = Integer.parseInt(args[0]);
         List<Integer> firstPolynomial = new ArrayList<>();
         args[1] = args[1].substring(1, args[1].length()-1);
@@ -14,6 +13,11 @@ public class Main {
         List<Integer> secondPolynomial = new ArrayList<>();
         Arrays.asList(args[2].split(",\\s*" )).forEach(factor -> secondPolynomial.add(Integer.valueOf(factor)));
         PolynomialTask polynomialTask = new PolynomialTask(n, firstPolynomial, secondPolynomial);
-        polynomialTask.printAllValuesToStandardOutput();
+        System.out.print("[");
+        System.out.print(polynomialTask.printMultipliedPoly()
+                + ", " +  polynomialTask.printSubtractedPoly()
+                + ", " + polynomialTask.printGcd());
+        System.out.print("]");
+
     }
 }

02-Wielomiany/src/PolynomialTask.java

@@ -1,134 +1,150 @@
-import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.List;
-import java.util.stream.Collectors;
 
 public class PolynomialTask {
     private int n;
 
-    private List<Integer> firstPolynomial;
+    private int[] firstPolynomialAsArray;
-    private List<Integer> secondPolynomial;
+    private int[] secondPolynomialAsArray;
 
     public PolynomialTask(int n, List<Integer> firstPoly, List<Integer> secondPoly) {
         this.n = n;
-        this.firstPolynomial = firstPoly;
+        this.firstPolynomialAsArray = parseListToArray(firstPoly);
-        this.secondPolynomial = secondPoly;
+        this.secondPolynomialAsArray = parseListToArray(secondPoly);
     }
 
-    public Integer[] multiplyPolynomials(List<Integer> firstPolynomial, List<Integer> secondPolynomial) {
+    private int[] parseListToArray(List<Integer> polynomial) {
-        int[] multiplied = new int[firstPolynomial.size() + secondPolynomial.size() - 1];
+        int[] result = new int[polynomial.size()];
-        int sizeOfFirstPoly = firstPolynomial.size();
+        for (int i = 0; i < polynomial.size(); i++) {
-        int sizeOfSecondPoly = secondPolynomial.size();
+            result[i] = polynomial.get(i);
+        }
+        return result;
+    }
+
+    private int[] multiplyPolynomials(int[] firstPolynomial, int[] secondPolynomial) {
+        int[] multiplied = new int[firstPolynomial.length + secondPolynomial.length - 1];
+        int sizeOfFirstPoly = firstPolynomial.length;
+        int sizeOfSecondPoly = secondPolynomial.length;
         for (int i = 0; i < sizeOfFirstPoly; i++) {
             for (int j = 0; j < sizeOfSecondPoly; j++)
-                multiplied[i + j] = (multiplied[i + j] + (firstPolynomial.get(i) * secondPolynomial.get(j))) % n;
+                multiplied[i + j] = (multiplied[i + j] + (firstPolynomial[i] * secondPolynomial[j])) % n;
         }
-        return Arrays.stream(multiplied).boxed().toArray(Integer[]::new);
+        return multiplied;
     }
 
-    public int[] moduloDividePolynomialsReturnQuotient(List<Integer> firstPoly, List<Integer> secondPoly) throws MultiplierNotFoundException, DivisionErrorException {
+    private int[] polyDiv(int[] polyOne, int[] polyTwo) {
-        int[] quotient = new int[firstPoly.size() + secondPoly.size()];
+        if (polyOne.length < polyTwo.length) {
-        int firstPolyDegree = firstPoly.size() - 1;
+            return null;
-        int secondPolyDegree = secondPoly.size() - 1;
-        List<Integer> polynomialAfterSubtract = firstPoly;
-
-
-        while (firstPolyDegree >= secondPolyDegree) {
-            polynomialAfterSubtract = calcQuotient(polynomialAfterSubtract, secondPoly, quotient);
-            firstPolyDegree = polynomialAfterSubtract.size() - 1;
         }
-
+        int firstPolyDeg = polyOne.length - 1;
-        int[] remainder = new int[polynomialAfterSubtract.size()];
+        int secondPolyDeg = polyTwo.length - 1;
-        for (int i = 0; i < polynomialAfterSubtract.size(); i++) {
+        int[] tempArr = new int[polyOne.length];
-            remainder[i] = polynomialAfterSubtract.get(i);
+        int[] result;
+        fillTemporaryArray(polyTwo, tempArr);
+        int tempMultiplier;
+        int shift = 0;
+        while (firstPolyDeg >= secondPolyDeg) {
+            parseNegativeElement(polyOne, firstPolyDeg);
+            tempMultiplier = findMultiplier(polyOne[firstPolyDeg], polyTwo[secondPolyDeg]);
+            tempArr = shiftValuesInArray(tempArr, shift);
+            tempArr = multiplyPolyByNumber(tempArr, tempMultiplier);
+            tempArr = moduloArray(tempArr);
+            polyOne = subtractTwoPolynomials(polyOne, tempArr);
+            firstPolyDeg--;
+            shift++;
         }
-        return remainder;
+        result = Arrays.copyOf(polyOne, shift - 1);
+        return result;
     }
 
-    private List<Integer> calcQuotient(List<Integer> firstPoly, List<Integer> secondPoly, int[] quotient) throws MultiplierNotFoundException, DivisionErrorException {
+    private void fillTemporaryArray(int[] polyTwo, int[] tempArr) {
-        int firstPolyDegree = firstPoly.size() - 1;
+        for (int i = 0; i < polyTwo.length; i++) {
-        int secondPolyDegree = secondPoly.size() - 1;
+            tempArr[tempArr.length - 1 - i] = polyTwo[polyTwo.length - 1 - i];
-        if (firstPolyDegree < secondPolyDegree) {
-            throw new DivisionErrorException();
         }
-        int quotientCoefficient;
-        if ((((float) firstPoly.get(firstPolyDegree) / (float) secondPoly.get(secondPolyDegree))) == Math.round(firstPoly.get(firstPolyDegree) / secondPoly.get(secondPolyDegree))) {
-            quotientCoefficient = firstPoly.get(firstPolyDegree) / secondPoly.get(secondPolyDegree);
-        } else {
-            quotientCoefficient = invElem(firstPoly.get(firstPolyDegree), secondPoly.get(secondPolyDegree));
-        }
-        quotient[firstPolyDegree - secondPolyDegree] += quotientCoefficient;
-        List<Integer> newPoly = generatePolyFromIndexAndValue(firstPolyDegree - secondPolyDegree, quotientCoefficient);
-        Integer[] multipliedPolynomials = multiplyPolynomials(newPoly, secondPoly);
-        List<Integer> polynomialAfterFirstDivide = new ArrayList<>(Arrays.asList(multipliedPolynomials));
-
-        return removeUnnecessaryZeros(subtractTwoPolynomials(firstPoly, polynomialAfterFirstDivide));
     }
 
-    private List<Integer> removeUnnecessaryZeros(List<Integer> polynomialAfterSubtract) {
+    private int[] subtractTwoPolynomials(int[] polyOne, int[] polyTwo) {
-        int amountOfZeros = 0;
+        int[] result = new int[polyOne.length];
-        for (int i = polynomialAfterSubtract.size() - 1; i >= 0; i--) {
+        for (int i = 0; i < polyOne.length; i++) {
-            if (polynomialAfterSubtract.get(i) == 0) {
+            result[i] = polyOne[i] - polyTwo[i];
-                amountOfZeros++;
-            } else {
-                break;
-            }
         }
-
+        return result;
-        polynomialAfterSubtract = polynomialAfterSubtract.subList(0, polynomialAfterSubtract.size() - amountOfZeros);
-        return polynomialAfterSubtract;
     }
 
-    private List<Integer> subtractTwoPolynomials(List<Integer> firstPoly, List<Integer> secondPoly) {
+    private int[] moduloArray(int[] array) {
-        List<Integer> subtractedPolynomial = new ArrayList<>(Collections.nCopies(firstPoly.size() + secondPoly.size(), 0));
+        for (int i = 0; i < array.length; i++) {
-        for (int index = firstPoly.size(); index >= 0; index--) {
+            array[i] = array[i] % n;
-            if (index < secondPoly.size()) {
-                subtractedPolynomial.set(index, firstPoly.get(index) - secondPoly.get(index));
-                parseNegativeElement(subtractedPolynomial, index);
-            }
         }
-        return subtractedPolynomial;
+        return array;
     }
 
-    private void parseNegativeElement(List<Integer> subtractedPolynomial, int index) {
+    private int[] multiplyPolyByNumber(int[] poly, int multiplier) {
-        while (subtractedPolynomial.get(index) < 0)
+        for (int i = 0; i < poly.length; i++) {
-            subtractedPolynomial.set(index, (subtractedPolynomial.get(index) * subtractedPolynomial.get(index)) % n);
+            poly[i] = poly[i] * multiplier;
-    }
+        }
-
-    private List<Integer> generatePolyFromIndexAndValue(int size, int quotientCoefficient) {
-        List<Integer> poly = new ArrayList<>(Collections.nCopies(size + 1, 0));
-        poly.set(size, quotientCoefficient);
         return poly;
     }
 
-    private int invElem(int a, int b) throws MultiplierNotFoundException {
+    private int[] shiftValuesInArray(int[] array, int amount) {
+        if (amount == 0) {
+            return array;
+        } else {
+            int[] res = new int[array.length];
+            System.arraycopy(array, amount, res, 0, array.length - amount);
+            for (int j = array.length - amount + 1; j < res.length; j++) {
+                res[j] = 0;
+            }
+            return res;
+        }
+    }
 
+    private void parseNegativeElement(int[] polyOne, int firstPolyDeg) {
+        while (polyOne[firstPolyDeg] < 0) {
+            polyOne[firstPolyDeg] = n + polyOne[firstPolyDeg];
+        }
+    }
+
+    private int findMultiplier(int a, int b) {
         for (int i = 0; i < n; i++) {
             if (a == (b * i) % n) {
                 return i;
             }
         }
-
+        return -1;
-        throw new MultiplierNotFoundException();
     }
 
-    public void printAllValuesToStandardOutput() throws DivisionErrorException, MultiplierNotFoundException {
+    public String printMultipliedPoly() {
-        List<List<Integer>> values = new ArrayList<>();
+        return Arrays.toString(multiplyPolynomials(firstPolynomialAsArray, secondPolynomialAsArray));
-        values.add(Arrays.asList(multiplyPolynomials(firstPolynomial, secondPolynomial)));
+    }
-        values.add(Arrays.stream(moduloDividePolynomialsReturnQuotient(firstPolynomial, secondPolynomial)).boxed().collect(Collectors.toList()));
+
-        try {
+    public String printSubtractedPoly() {
-            values.add(gcd(firstPolynomial, secondPolynomial));
+        int[] result = polyDiv(firstPolynomialAsArray, secondPolynomialAsArray);
-        } catch (MultiplierNotFoundException e) {
+        if (result == null) {
+            return "Division Error";
+        } else if (result.length == 0) {
+            return "[0]";
+        } else {
+            return Arrays.toString(polyDiv(firstPolynomialAsArray, secondPolynomialAsArray));
         }
-        System.out.println(values);
     }
 
-    private List<Integer> gcd(List<Integer> polyOne, List<Integer> polyTwo) throws MultiplierNotFoundException, DivisionErrorException {
+    public String printGcd() {
-        if (polyTwo.isEmpty()) return polyOne;
+        int[] gcd = gcd(firstPolynomialAsArray, secondPolynomialAsArray);
-        List<Integer> poly = Arrays.stream(moduloDividePolynomialsReturnQuotient(polyOne, polyTwo)).boxed().collect(Collectors.toList());
+        if (gcd == null) {
-        return gcd(polyTwo, poly);
+            return "Division Error";
+        } else
+            return Arrays.toString(gcd);
+    }
 
+    private int[] gcd(int[] firstPoly, int[] secondPoly) {
+        if (secondPoly.length == 0) {
+            return firstPoly;
+        }
+        if (firstPoly.length >= secondPoly.length) {
+            return gcd(secondPoly, polyDiv(firstPoly, secondPoly));
+        } else {
+            return gcd(secondPoly, polyDiv(secondPoly, firstPoly));
+        }
     }
 
 }