This program checks whether a given number is a Happy Number. It repeatedly replaces the
number with the sum of the squares of its digits until it either becomes 1 (happy) or enters a cycle
that never reaches 1 (unhappy). For example: 1912+92 = 8282 + 2² = 68 → 62 +8² = 100
→12+02+021 → Happy.
->
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class happyNumber {
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public static void main(String[] args) {
Scanner sc
System.out.print("Enter a number to check: ");
int num sc.nextInt();
if (isHappy (num)) {
Scanner(System.in);
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System.out.println(num + " is a Happy Number.");
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} else {
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System.out.println(num + " is NOT a Happy Number.");
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}
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}
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public static boolean isHappy (int n) {
int slow = n;
int fast sumOfSquares (n);
while (fast != 1 && slow != fast) {
}
slow sumofSquares (slow);
fast sumofSquares (sumOfSquares (fast));
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