Add bit map code

jbee37142 · jbee37142 · commit 19670fced77b · 2017-06-01T10:57:55.000+09:00
diff --git a/src/test/java/bit/BitMapTest.java b/src/test/java/bit/BitMapTest.java
@@ -0,0 +1,44 @@
+package bit;
+
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+public class BitMapTest {
+
+    /*
+        TASK
+        O(1)으로 해당 데이터가 존재하는지 판단한다.
+     */
+
+    @Test
+    public void test() {
+        BitMap bitMap = new BitMap();
+        bitMap.store("1234567");
+        assertThat(bitMap.exist("1234567"), is(true));
+        assertThat(bitMap.exist("1234568"), is(false));
+    }
+
+    public class BitMap {
+        public int[] cache;
+
+        public BitMap() {
+            cache = new int[(10 * 1000 * 1000) / 32];
+        }
+
+        public void store(String data) {
+            int dataInt = Integer.parseInt(data);
+            int arrIndex = dataInt / 32;
+            int byteIndex = dataInt % 32;
+            cache[arrIndex] = cache[arrIndex] | (1 << byteIndex);
+        }
+
+        public boolean exist(String data) {
+            int dataInt = Integer.parseInt(data);
+            int arrIndex = dataInt / 32;
+            int byteIndex = dataInt % 32;
+            return (cache[arrIndex] & (1 << byteIndex)) != 0;
+        }
+    }
+}
diff --git a/src/test/java/search/BinarySearchTest.java b/src/test/java/search/BinarySearchTest.java
@@ -0,0 +1,7 @@
+package search;
+
+/**
+ * Created by Jbee on 2017. 6. 1..
+ */
+public class BinarySearchTest {
+}
