Merge branch 'master' into fix/binary-search-2d-array-bounds

Author: DenizAltunkapan

pom.xml

@@ -61,7 +61,7 @@
         <plugins>
             <plugin>
                 <artifactId>maven-surefire-plugin</artifactId>
-                <version>3.6.0</version>
+                <version>3.6.1</version>
                 <configuration>
                     <forkNode implementation="org.apache.maven.plugin.surefire.extensions.SurefireForkNodeFactory"/>
                 </configuration>
@@ -82,7 +82,7 @@
             <plugin>
                 <groupId>org.jacoco</groupId>
                 <artifactId>jacoco-maven-plugin</artifactId>
-                <version>0.8.15</version>
+                <version>0.8.16</version>
                 <executions>
                     <execution>
                         <goals>

src/main/java/com/thealgorithms/maths/BinomialCoefficient.java

@@ -21,9 +21,14 @@ private BinomialCoefficient() {
      * @param numberOfObjects Number of objects to be chosen from total_objects
      * @return number of ways in which no_of_objects objects can be chosen from total_objects
      *     objects
+     * @throws IllegalArgumentException if totalObjects or numberOfObjects is negative
      */
 
     public static int binomialCoefficient(int totalObjects, int numberOfObjects) {
+        if (totalObjects < 0 || numberOfObjects < 0) {
+            throw new IllegalArgumentException("Arguments must be non-negative.");
+        }
+
         // Base Case
         if (numberOfObjects > totalObjects) {
             return 0;

src/main/java/com/thealgorithms/searches/RabinKarpAlgorithm.java

@@ -13,9 +13,14 @@ public static int search(String pattern, String text, int primeNumber) {
         int index = -1; // -1 here represents not found
         int patternLength = pattern.length();
         int textLength = text.length();
-        int hashForPattern = 0;
-        int hashForText = 0;
-        int h = 1;
+        if (patternLength > textLength) {
+            return index;
+        }
+
+        // long, so hash * ALPHABET_SIZE cannot overflow for large primes such as 1_000_000_007
+        long hashForPattern = 0;
+        long hashForText = 0;
+        long h = 1;
 
         // The value of h would be "pow(d, patternLength-1)%primeNumber"
         for (int i = 0; i < patternLength - 1; i++) {

src/test/java/com/thealgorithms/maths/BinomialCoefficientTest.java

@@ -1,6 +1,7 @@
 package com.thealgorithms.maths;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import org.junit.jupiter.api.Test;
 
@@ -12,5 +13,14 @@ void testBinomialCoefficient() {
         assertEquals(792, BinomialCoefficient.binomialCoefficient(12, 5));
         assertEquals(84, BinomialCoefficient.binomialCoefficient(9, 3));
         assertEquals(1, BinomialCoefficient.binomialCoefficient(17, 17));
+        assertEquals(0, BinomialCoefficient.binomialCoefficient(5, 6));
+        assertEquals(1, BinomialCoefficient.binomialCoefficient(0, 0));
+    }
+
+    @Test
+    void testNegativeInputs() {
+        assertThrows(IllegalArgumentException.class, () -> BinomialCoefficient.binomialCoefficient(5, -1));
+        assertThrows(IllegalArgumentException.class, () -> BinomialCoefficient.binomialCoefficient(-1, 5));
+        assertThrows(IllegalArgumentException.class, () -> BinomialCoefficient.binomialCoefficient(-5, -2));
     }
 }

src/test/java/com/thealgorithms/matrix/matrixexponentiation/FibonacciTest.java

@@ -0,0 +1,34 @@
+package com.thealgorithms.matrix.matrixexponentiation;
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+
+import java.math.BigDecimal;
+import org.junit.jupiter.api.Test;
+class FibonacciTest {
+    private static BigDecimal[][] matrix(String a, String b, String c, String d) {
+        return new BigDecimal[][] {{new BigDecimal(a), new BigDecimal(b)}, {new BigDecimal(c), new BigDecimal(d)}};
+    }
+    @Test
+    void testFibZeroReturnsIdentityMatrix() {
+        assertArrayEquals(matrix("1", "0", "0", "1"), Fibonacci.fib(0));
+    }
+    @Test
+    void testFibOne() {
+        assertArrayEquals(matrix("1", "1", "1", "0"), Fibonacci.fib(1));
+    }
+    @Test
+    void testFibEvenInput() {
+        assertArrayEquals(matrix("2", "1", "1", "1"), Fibonacci.fib(2));
+    }
+    @Test
+    void testFibOddInput() {
+        assertArrayEquals(matrix("3", "2", "2", "1"), Fibonacci.fib(3));
+    }
+    @Test
+    void testFibTen() {
+        assertArrayEquals(matrix("89", "55", "55", "34"), Fibonacci.fib(10));
+    }
+    @Test
+    void testFibLargeInput() {
+        assertArrayEquals(matrix("20365011074", "12586269025", "12586269025", "7778742049"), Fibonacci.fib(50));
+    }
+}

src/test/java/com/thealgorithms/searches/RabinKarpAlgorithmTest.java

@@ -8,7 +8,7 @@
 class RabinKarpAlgorithmTest {
 
     @ParameterizedTest
-    @CsvSource({"This is an example for rabin karp algorithmn, algorithmn, 101", "AAABBDDG, AAA, 137", "AAABBCCBB, BBCC, 101", "AAABBCCBB, BBCC, 131", "AAAABBBBCCC, CCC, 41", "ABCBCBCAAB, AADB, 293", "Algorithm The Algorithm, Algorithm, 101"})
+    @CsvSource({"This is an example for rabin karp algorithmn, algorithmn, 101", "AAABBDDG, AAA, 137", "AAABBCCBB, BBCC, 101", "AAABBCCBB, BBCC, 131", "AAAABBBBCCC, CCC, 41", "ABCBCBCAAB, AADB, 293", "Algorithm The Algorithm, Algorithm, 101", "nzdjsjggwx, jggw, 1000000007", "AB, ABC, 101"})
     void rabinKarpAlgorithmTestExample(String txt, String pat, int q) {
         int indexFromOurAlgorithm = RabinKarpAlgorithm.search(pat, txt, q);
         int indexFromLinearSearch = txt.indexOf(pat);