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

57 lines
1.2 KiB
Java

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();
}
}