September 2017 Update

This commit is contained in:
Ingy döt Net 2017-09-23 10:01:46 +02:00
parent bba7bfd280
commit ba8067c3b7
14570 changed files with 153136 additions and 63871 deletions

View file

@ -1,30 +1,27 @@
class BigRationalFindPerfectNumbers {
public static void main(String[] args) {
System.out.println("Running BigRational built-in tests");
if (BigRational.testFeatures()) {
int MAX_NUM = (1 << 19);
System.out.println();
System.out.println("Searching for perfect numbers in the range [1, " + (MAX_NUM - 1) + "]");
BigRational TWO = BigRational.valueOf(2);
for (int i = 1; i < MAX_NUM; i++) {
BigRational reciprocalSum = BigRational.ONE;
if (i > 1)
reciprocalSum = reciprocalSum.add(BigRational.valueOf(i).reciprocal());
int maxDivisor = (int)Math.sqrt(i);
if (maxDivisor >= i)
maxDivisor--;
for (int divisor = 2; divisor <= maxDivisor; divisor++) {
if ((i % divisor) == 0) {
reciprocalSum = reciprocalSum.add(BigRational.valueOf(divisor).reciprocal());
int dividend = i / divisor;
if (divisor != dividend)
reciprocalSum = reciprocalSum.add(BigRational.valueOf(dividend).reciprocal());
}
public class BigRationalFindPerfectNumbers {
public static void main(String[] args) {
int MAX_NUM = 1 << 19;
System.out.println("Searching for perfect numbers in the range [1, " + (MAX_NUM - 1) + "]");
BigRational TWO = BigRational.valueOf(2);
for (int i = 1; i < MAX_NUM; i++) {
BigRational reciprocalSum = BigRational.ONE;
if (i > 1)
reciprocalSum = reciprocalSum.add(BigRational.valueOf(i).reciprocal());
int maxDivisor = (int) Math.sqrt(i);
if (maxDivisor >= i)
maxDivisor--;
for (int divisor = 2; divisor <= maxDivisor; divisor++) {
if (i % divisor == 0) {
reciprocalSum = reciprocalSum.add(BigRational.valueOf(divisor).reciprocal());
int dividend = i / divisor;
if (divisor != dividend)
reciprocalSum = reciprocalSum.add(BigRational.valueOf(dividend).reciprocal());
}
}
if (reciprocalSum.equals(TWO))
System.out.println(String.valueOf(i) + " is a perfect number");
}
if (reciprocalSum.equals(TWO))
System.out.println(String.valueOf(i) + " is a perfect number");
}
}
return;
}
}