Initial data commit

Task/Population-count/Java/population-count.java

@@ -0,0 +1,56 @@
+import java.math.BigInteger;
+
+public class PopCount {
+    public static void main(String[] args) {
+	{ // with int
+	    System.out.print("32-bit integer: ");
+	    int n = 1;
+	    for (int i = 0; i < 20; i++) {
+		System.out.printf("%d ", Integer.bitCount(n));
+		n *= 3;
+	    }
+	    System.out.println();
+	}
+	{ // with long
+	    System.out.print("64-bit integer: ");
+	    long n = 1;
+	    for (int i = 0; i < 30; i++) {
+		System.out.printf("%d ", Long.bitCount(n));
+		n *= 3;
+	    }
+	    System.out.println();
+	}
+	{ // with BigInteger
+	    System.out.print("big integer   : ");
+	    BigInteger n = BigInteger.ONE;
+	    BigInteger three = BigInteger.valueOf(3);
+	    for (int i = 0; i < 30; i++) {
+		System.out.printf("%d ", n.bitCount());
+		n = n.multiply(three);
+	    }
+	    System.out.println();
+	}
+
+	int[] od = new int[30];
+	int ne = 0, no = 0;
+	System.out.print("evil   : ");
+	for (int n = 0; ne+no < 60; n++) {
+	    if ((Integer.bitCount(n) & 1) == 0) {
+		if (ne < 30) {
+		    System.out.printf("%d ", n);
+		    ne++;
+		}
+	    } else {
+		if (no < 30) {
+		    od[no++] = n;
+		}
+	    }
+	}
+	System.out.println();
+	System.out.print("odious : ");
+	for (int n : od) {
+	    System.out.printf("%d ", n);
+	}
+	System.out.println();
+    }
+}