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Format code with prettier (#3375)

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2022-10-03 17:23:00 +08:00
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parent 32b9b11ed5
commit e96f567bfc
464 changed files with 11483 additions and 6189 deletions
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95
src/main/java/com/thealgorithms/maths/KaprekarNumbers.java
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@ -1,53 +1,68 @@
package com.thealgorithms.maths;
import java.math.BigInteger;
import java.util.*;
public class KaprekarNumbers {
/* This program demonstrates if a given number is Kaprekar Number or not.
/* This program demonstrates if a given number is Kaprekar Number or not.
Kaprekar Number: A Kaprekar number is an n-digit number which its square can be split into two parts where the right part has n
digits and sum of these parts is equal to the original number. */
// Provides a list of kaprekarNumber in a range
public static ArrayList<Long> kaprekarNumberInRange(long start, long end) throws Exception {
long n = end-start;
if (n <0) throw new Exception("Invalid range");
ArrayList<Long> list = new ArrayList<>();
// Provides a list of kaprekarNumber in a range
public static ArrayList<Long> kaprekarNumberInRange(long start, long end)
throws Exception {
long n = end - start;
if (n < 0) throw new Exception("Invalid range");
ArrayList<Long> list = new ArrayList<>();
for (long i = start; i <= end; i++) {
if (isKaprekarNumber(i)) list.add(i);
}
for (long i = start; i <= end; i++) {
if (isKaprekarNumber(i)) list.add(i);
}
return list;
}
// Checks whether a given number is Kaprekar Number or not
public static boolean isKaprekarNumber(long num) {
String number = Long.toString(num);
BigInteger originalNumber = new BigInteger(number);
BigInteger numberSquared = originalNumber.multiply(originalNumber);
if(number.length() == numberSquared.toString().length()){
return number.equals(numberSquared.toString());
}
else{
BigInteger leftDigits1 = new BigInteger("0");
BigInteger leftDigits2;
if(numberSquared.toString().contains("0")){
leftDigits1 = new BigInteger(
numberSquared.toString().
substring(0, numberSquared.toString().indexOf("0")
)
);
}
leftDigits2 = new BigInteger(
numberSquared.toString()
.substring(0, (numberSquared.toString().length() - number.length()))
);
BigInteger rightDigits = new BigInteger(numberSquared.toString().substring(numberSquared.toString().length() - number.length()));
String x = leftDigits1.add(rightDigits).toString();
String y = leftDigits2.add(rightDigits).toString();
return (number.equals(x)) || (number.equals(y));
}
}
return list;
}
// Checks whether a given number is Kaprekar Number or not
public static boolean isKaprekarNumber(long num) {
String number = Long.toString(num);
BigInteger originalNumber = new BigInteger(number);
BigInteger numberSquared = originalNumber.multiply(originalNumber);
if (number.length() == numberSquared.toString().length()) {
return number.equals(numberSquared.toString());
} else {
BigInteger leftDigits1 = new BigInteger("0");
BigInteger leftDigits2;
if (numberSquared.toString().contains("0")) {
leftDigits1 =
new BigInteger(
numberSquared
.toString()
.substring(0, numberSquared.toString().indexOf("0"))
);
}
leftDigits2 =
new BigInteger(
numberSquared
.toString()
.substring(
0,
(
numberSquared.toString().length() -
number.length()
)
)
);
BigInteger rightDigits = new BigInteger(
numberSquared
.toString()
.substring(
numberSquared.toString().length() - number.length()
)
);
String x = leftDigits1.add(rightDigits).toString();
String y = leftDigits2.add(rightDigits).toString();
return (number.equals(x)) || (number.equals(y));
}
}
}