correct CRC output type

02-Wielomiany/src/DivisionErrorException.java

@@ -1,5 +0,0 @@
-public class DivisionErrorException extends Throwable {
-    public DivisionErrorException() {
-        System.out.println("Division error!");
-    }
-}

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

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

02-Wielomiany/src/Main.java

@@ -1,23 +0,0 @@
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.List;
-
-public class Main {
-
-    public static void main(String[] args){
-        int n = Integer.parseInt(args[0]);
-        List<Integer> firstPolynomial = new ArrayList<>();
-        args[1] = args[1].substring(1, args[1].length()-1);
-        args[2] = args[2].substring(1, args[2].length()-1);
-        Arrays.asList(args[1].split( ",\\s*" )).forEach(factor -> firstPolynomial.add(Integer.valueOf(factor)));
-        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);
-        System.out.print("[");
-        System.out.print(polynomialTask.printMultipliedPoly()
-                + ", " +  polynomialTask.printSubtractedPoly()
-                + ", " + polynomialTask.printGcd());
-        System.out.print("]");
-
-    }
-}

02-Wielomiany/src/MultiplierNotFoundException.java

@@ -1,5 +0,0 @@
-public class MultiplierNotFoundException extends Throwable {
-    public MultiplierNotFoundException() {
-        System.out.println("DivisionError");
-    }
-}

02-Wielomiany/src/PolynomialTask.java

@@ -1,150 +0,0 @@
-import java.util.Arrays;
-import java.util.List;
-
-public class PolynomialTask {
-    private int n;
-
-    private int[] firstPolynomialAsArray;
-    private int[] secondPolynomialAsArray;
-
-    public PolynomialTask(int n, List<Integer> firstPoly, List<Integer> secondPoly) {
-        this.n = n;
-        this.firstPolynomialAsArray = parseListToArray(firstPoly);
-        this.secondPolynomialAsArray = parseListToArray(secondPoly);
-    }
-
-    private int[] parseListToArray(List<Integer> polynomial) {
-        int[] result = new int[polynomial.size()];
-        for (int i = 0; i < polynomial.size(); i++) {
-            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[i] * secondPolynomial[j])) % n;
-        }
-        return multiplied;
-    }
-
-    private int[] polyDiv(int[] polyOne, int[] polyTwo) {
-        if (polyOne.length < polyTwo.length) {
-            return null;
-        }
-        int firstPolyDeg = polyOne.length - 1;
-        int secondPolyDeg = polyTwo.length - 1;
-        int[] tempArr = new int[polyOne.length];
-        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++;
-        }
-        result = Arrays.copyOf(polyOne, shift - 1);
-        return result;
-    }
-
-    private void fillTemporaryArray(int[] polyTwo, int[] tempArr) {
-        for (int i = 0; i < polyTwo.length; i++) {
-            tempArr[tempArr.length - 1 - i] = polyTwo[polyTwo.length - 1 - i];
-        }
-    }
-
-    private int[] subtractTwoPolynomials(int[] polyOne, int[] polyTwo) {
-        int[] result = new int[polyOne.length];
-        for (int i = 0; i < polyOne.length; i++) {
-            result[i] = polyOne[i] - polyTwo[i];
-        }
-        return result;
-    }
-
-    private int[] moduloArray(int[] array) {
-        for (int i = 0; i < array.length; i++) {
-            array[i] = array[i] % n;
-        }
-        return array;
-    }
-
-    private int[] multiplyPolyByNumber(int[] poly, int multiplier) {
-        for (int i = 0; i < poly.length; i++) {
-            poly[i] = poly[i] * multiplier;
-        }
-        return poly;
-    }
-
-    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;
-    }
-
-    public String printMultipliedPoly() {
-        return Arrays.toString(multiplyPolynomials(firstPolynomialAsArray, secondPolynomialAsArray));
-    }
-
-    public String printSubtractedPoly() {
-        int[] result = polyDiv(firstPolynomialAsArray, secondPolynomialAsArray);
-        if (result == null) {
-            return "Division Error";
-        } else if (result.length == 0) {
-            return "[0]";
-        } else {
-            return Arrays.toString(polyDiv(firstPolynomialAsArray, secondPolynomialAsArray));
-        }
-    }
-
-    public String printGcd() {
-        int[] gcd = gcd(firstPolynomialAsArray, secondPolynomialAsArray);
-        if (gcd == null) {
-            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));
-        }
-    }
-
-}

03-CRC.md

@@ -4,10 +4,12 @@ Napisać program, który dla wiadomości `M` w formie tekstowej ASCII (tj. `8` b
 
 1. utworzy FCS (*Frame Check Sequence*) długości `16` bitów zgodnie z algorytmem **D-1.1**;
   - INPUT: `M` - tablica znaków ASCII długości `n-2`;
-  - OUTPUT: `N` - tablica znaków ASCII długości `n`, która zawiera oryginalną wiadomość `M` na pierwszych `n-2` miejscach, zaś ostatnie zawierają FCS interpretowanymi jako dwa znaki (po 8 bitów każdy).
+  - OUTPUT: `N` - tablica 8-bitowych liczb (`unsigned char`) długości `n`, która zawiera oryginalną wiadomość `M` na pierwszych `n-2` miejscach, zaś ostatnie dwa zawierają FCS.
 2. pozwoli sprawdzić, czy dana ramka (tj. wiadomość + FCS) zawiera poprawną treść (zgodnie z **D-1.2**;
-  - INPUT: `N` - tablica znaków ASCII długości `n`
-  - OUTPUT: `true` jeśli dwa ostatnie znaki `N` odpowiadają FCS wiadomości `M = N[0:n-2]`, `false` w przeciwnym wypadku;
+  - INPUT: `N` - tablica 8-bitowych liczb (`unsigned char`) długości `n` (np. w formacie hex)
+  - OUTPUT: `true` jeśli dwie ostatnie liczby tablicy `N` odpowiadają FCS wiadomości `M = N[0:n-2]` (interpretowanej jako tablica typu `char`), `false` w przeciwnym wypadku;
+
+UWAGA: Program w punkcie **2** powinien być w stanie zweryfikować output z punktu **1**!
 
 Źródło: [Report: Telemetry Summary of Concept and Rationale](http://mtc-m16c.sid.inpe.br/col/sid.inpe.br/mtc-m18@80/2009/07.15.17.25/doc/CCSDS%20100.0-G-1.pdf), CCSDS 100.0-G-1 Report Concerning Space.
 

04-Ilorazy-pierścienia-wielomianów.md

@@ -0,0 +1,48 @@
+## Zadanie
+
+Napisać program, który dla pierścienia `ℤ/nℤ[x]/(f = a₀ + a₁x¹+ ...+ aₖxᵏ)` znajdzie wszystkie
+
+  1. elementy odwracalne,
+  2. dzielniki zera,
+  3. elementy nilpotentne,
+  4. elementy idempotentne.
+
+  - INPUT: `n [a₀,a₁,...,aₖ]`
+  - OUTPUT: lista zawierająca cztery powyższe listy elementów (wielomianów, podanych jako listy współczynników)
+
+### Przykłady:
+
+1. `ℤ/2ℤ[x]/(x² + x + 1)`, który jest ciałem, tzn. `0` jest jedynym elementem nilpotentnym i jedynym dzielnikiem zera:
+   * INPUT: `2 [1,1,1]` 
+   * OUTPUT: 
+
+```shell
+[
+	[[1], [0,1], [0,1], [1,1]], # odwracalne
+	[[0]],	# dzielniki zera
+	[[0]],	# nilpotenty
+	[[1]]	# idempotenty
+]
+```
+
+1. `ℤ/5ℤ[x]/(2x³ + 2x² + x + 1)`
+   * INPUT: `3, [1,1,2,2]` 
+   * OUTPUT:
+
+```sh
+[
+	[[1], [2], [0, 1], [0, 2], [0, 0, 1], [1, 0, 1], [2, 1, 1], [2, 2, 1], [0, 0, 2], [2, 0, 2], [1, 1, 2], [1, 2, 2]], # odwracalne
+	[[0], [1, 1], [2, 1], [1, 2], [2, 2], [2, 0, 1], [0, 1, 1], [1, 1, 1], [0, 2, 1], [1, 2, 1], [1, 0, 2], [0, 1, 2], [2, 1, 2], [0, 2, 2], [2, 2, 2]], # dzielniki zera
+	[[0], [2, 0, 1], [1, 0, 2]], # nilpotenty
+	[[0], [1], [1, 2, 1], [0, 1, 2]] # idempotenty
+]
+```
+
+### Warunki punktacji
+* program musi być typu wsadowego, tj. uruchamiany z linii komend;
+* program musi się działać (i kompilować) na serwerze [LTS](https://laboratoria.wmi.amu.edu.pl/en/uslugi/serwer-terminalowy/lts)
+
+UWAGA: **NIE** przyjmuję squashed pulls (z jednym commitem)
+
+### Termin
+28.06.2018

Zadanie-03/.idea/vcs.xml

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="VcsDirectoryMappings">
-    <mapping directory="$PROJECT_DIR$/.." vcs="Git" />
-  </component>
-</project>

Zadanie-03/Zadanie-03.iml

@@ -1,12 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<module type="JAVA_MODULE" version="4">
-  <component name="NewModuleRootManager" inherit-compiler-output="true">
-    <exclude-output />
-    <content url="file://$MODULE_DIR$">
-      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
-    </content>
-    <orderEntry type="inheritedJdk" />
-    <orderEntry type="sourceFolder" forTests="false" />
-  </component>
-</module>
-

Zadanie-03/src/com/tylkowski/crc/CrcTask.java

@@ -1,222 +0,0 @@
-package com.tylkowski.crc;
-
-import java.util.Arrays;
-
-class CrcTask {
-    private String message;
-    private short[] messageAsShortArray;
-    private short[] polyGenerator;
-    private String rawMessage;
-
-    CrcTask(String message, String rawMessage) {
-        this.message = formatMessage(toBinary(message)) + "0000000000000000";
-        this.rawMessage = rawMessage;
-        createGeneratingPolynomial();
-    }
-
-    private String toBinary(String s) {
-        byte[] bytes = s.getBytes();
-        StringBuilder binary = new StringBuilder();
-        for (byte b : bytes) {
-            int val = b;
-            for (int i = 0; i < 8; i++) {
-                binary.append((val & 128) == 0 ? 0 : 1);
-                val <<= 1;
-            }
-        }
-        return binary.toString();
-    }
-
-    private String formatMessage(String message) {
-        int firstNonZeroVal = 0;
-        boolean found = false;
-        StringBuilder validString = new StringBuilder();
-        while (!found && firstNonZeroVal < message.length()) {
-            if (message.charAt(firstNonZeroVal) == 48) {
-                firstNonZeroVal++;
-            } else {
-                found = true;
-            }
-        }
-
-        for (int i = firstNonZeroVal; i < message.length(); i++) {
-            if (message.charAt(i) == 48) {
-                validString.append(0);
-            } else {
-                validString.append(1);
-            }
-        }
-        StringBuilder msg = new StringBuilder(validString.toString());
-        while (msg.length() % 8 != 0) {
-            msg.insert(0, "0");
-        }
-
-        return msg.toString();
-    }
-
-    private String generateFCS() {
-        while (true) {
-            if (messageAsShortArray[0] == 0) {
-                messageAsShortArray = Arrays.copyOfRange(messageAsShortArray, 1, messageAsShortArray.length);
-            } else {
-                short[] piece = Arrays.copyOfRange(messageAsShortArray, 0, Math.min(polyGenerator.length, messageAsShortArray.length));
-                if (piece.length < polyGenerator.length) {
-                    fillPolynomial(piece);
-                    return "" + getCharFromShortArray(piece, 0, 8) + getCharFromShortArray(piece, piece.length - 8, piece.length);
-                }
-                short[] remainder = calcXOR(piece, polyGenerator);
-                remainder = removeUnecessaryZeros(remainder);
-                messageAsShortArray = createMessageFromRemainderAndPartFromOldMessage(remainder, messageAsShortArray);
-            }
-
-
-        }
-
-    }
-
-    private short[] createMessageFromRemainderAndPartFromOldMessage(short[] remainder, short[] msg) {
-        short[] tempArr = new short[remainder.length + msg.length - polyGenerator.length];
-        System.arraycopy(remainder, 0, tempArr, 0, remainder.length);
-        int diff = polyGenerator.length - remainder.length;
-        System.arraycopy(msg, remainder.length + diff, tempArr, remainder.length, msg.length - diff - remainder.length);
-        msg = tempArr;
-        return msg;
-    }
-
-    private short[] removeUnecessaryZeros(short[] remainder) {
-        int firstNonZeroVal = 0;
-        boolean found = false;
-        while (!found && firstNonZeroVal < remainder.length) {
-            if (remainder[firstNonZeroVal] == 0) {
-                firstNonZeroVal++;
-            } else {
-                found = true;
-            }
-        }
-        return Arrays.copyOfRange(remainder, firstNonZeroVal, remainder.length);
-    }
-
-    private short[] calcXOR(short[] chunk, short[] polyGenerator) {
-        int a = Integer.parseInt(shortArrayToBinaryString(chunk), 2);
-        int b = Integer.parseInt(shortArrayToBinaryString(polyGenerator), 2);
-        String binaryString = Integer.toBinaryString(a ^ b);
-        return convertBinaryStringToShortArray(binaryString);
-    }
-
-    private String shortArrayToBinaryString(short[] value) {
-        StringBuilder binaryString = new StringBuilder();
-        for (Short a : value) {
-            binaryString.append(a);
-        }
-        return binaryString.toString();
-    }
-
-    private char getCharFromShortArray(short[] chunk, int from, int to) {
-        short[] sign = Arrays.copyOfRange(chunk, from, to);
-        int character = Integer.parseInt(shortArrayToBinaryString(sign), 2);
-//        System.out.println(character);
-        return (char) character;
-    }
-
-    private void fillPolynomial(short[] chunk) {
-        while (chunk.length % 8 != 0) {
-            chunk = addZeroAtBeginningOfArray(chunk);
-        }
-    }
-
-    private short[] addZeroAtBeginningOfArray(short[] chunk) {
-        short[] letterTemp = new short[chunk.length + 1];
-        letterTemp[0] = 0;
-        System.arraycopy(chunk, 0, letterTemp, 1, chunk.length);
-        return letterTemp;
-    }
-
-    private void convertMessageToBinaryShortArray() {
-        messageAsShortArray = new short[message.length()];
-        for (int i = 0; i < polyGenerator.length; i++) {
-            if (message.charAt(i) == 48) {
-                messageAsShortArray[i] = 0;
-            } else {
-                messageAsShortArray[i] = 1;
-            }
-        }
-    }
-
-    private short[] convertBinaryStringToShortArray(String binaryString) {
-        short[] shortArray = new short[binaryString.length()];
-        for (int i = 0; i < binaryString.length(); i++) {
-            if (binaryString.charAt(i) == 48) {
-                shortArray[i] = 0;
-            } else {
-                shortArray[i] = 1;
-            }
-        }
-        return shortArray;
-    }
-
-    private void createGeneratingPolynomial() {
-        polyGenerator = new short[17];
-        for (int i = 0; i < 17; i++) {
-            polyGenerator[i] = 0;
-        }
-        polyGenerator[0] = 1;
-        polyGenerator[4] = 1;
-        polyGenerator[11] = 1;
-        polyGenerator[16] = 1;
-    }
-
-    private short[] swapPolynomialValues(short[] poly) {
-        for (int i = 0; i < polyGenerator.length - 1; i++) {
-            poly[i] = (short) ((poly[i] + 1) % 2);
-        }
-        return poly;
-    }
-
-    String encode() {
-        convertMessageToBinaryShortArray();
-        messageAsShortArray = swapPolynomialValues(messageAsShortArray);
-        return rawMessage + generateFCS();
-    }
-
-    boolean decode(String encodedString) {
-        encodedString = toBinary(encodedString);
-        encodedString = fillPolyTo8(encodedString);
-        short[] encodedShortArray = convertBinaryStringToShortArray(encodedString);
-        encodedShortArray = swapPolynomialValues(encodedShortArray);
-        while (true) {
-            if (shortArrayContains(encodedShortArray, 1)) {
-                return true;
-            }
-
-            if (encodedShortArray[0] == 0) {
-                encodedShortArray = Arrays.copyOfRange(encodedShortArray, 1, encodedShortArray.length);
-            } else {
-                short[] piece = Arrays.copyOfRange(encodedShortArray, 0, Math.min(polyGenerator.length, encodedShortArray.length));
-                if (piece.length < polyGenerator.length) {
-                    return false;
-                }
-
-                short[] remainder = calcXOR(piece, polyGenerator);
-                remainder = removeUnecessaryZeros(remainder);
-                encodedShortArray = createMessageFromRemainderAndPartFromOldMessage(remainder, encodedShortArray);
-            }
-        }
-    }
-
-    private boolean shortArrayContains(short[] encodedShortArray, int value) {
-        for (short item : encodedShortArray) {
-            if (item == value) {
-                return true;
-            }
-        }
-        return false;
-    }
-
-    private String fillPolyTo8(String encodedString) {
-        StringBuilder stringBuilder = new StringBuilder(encodedString);
-        while (stringBuilder.length() % 8 != 0) {
-            stringBuilder.insert(0, "0");
-        }
-        return stringBuilder.toString();
-    }
-}

Zadanie-03/src/com/tylkowski/crc/Main.java

@@ -1,15 +0,0 @@
-package com.tylkowski.crc;
-
-public class Main {
-
-    public static void main(String[] args) {
-        // ex. in command line type "a"
-        CrcTask crcTask = new CrcTask(args[0], args[0]);
-        System.out.println(crcTask.encode());
-        String input = crcTask.encode();
-        if (input.length() >= 3) System.out.println(crcTask.decode(input));
-
-    }
-
-
-}