add jump search algorithm

Author: realDuYuanChao

Searches/JumpSearch.java

@@ -0,0 +1,39 @@
+package Searches;
+
+public class JumpSearch implements SearchAlgorithm {
+
+    public static void main(String[] args) {
+        JumpSearch jumpSearch = new JumpSearch();
+        Integer[] array = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+        for (int i = 0; i < array.length; i++) {
+            assert jumpSearch.find(array, i) == i;
+        }
+        assert jumpSearch.find(array, -1) == -1;
+        assert jumpSearch.find(array, 11) == -1;
+    }
+
+    /**
+     * Jump Search algorithm implements
+     *
+     * @param array the array contains elements
+     * @param key   to be searched
+     * @return index of {@code key} if found, otherwise <tt>-1</tt>
+     */
+    @Override
+    public <T extends Comparable<T>> int find(T[] array, T key) {
+        int length = array.length; /* length of array */
+        int blockSize = (int) Math.sqrt(length); /* block size to be jumped */
+
+        int limit = blockSize;
+        while (key.compareTo(array[limit]) > 0 && limit < array.length - 1) {
+            limit = Math.min(limit + blockSize, array.length - 1);
+        }
+
+        for (int i = limit - blockSize; i <= limit; i++) {
+            if (array[i] == key) { /* execute linear search */
+                return i;
+            }
+        }
+        return -1; /* not found */
+    }
+}