42 lines
1.3 KiB
Java
42 lines
1.3 KiB
Java
/*
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A perfect number is a positive integer that is equal to the sum
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of its proper positive divisors, that is, the sum of its positive
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divisors excluding the number itself. Equivalently, a perfect number
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is a number that is half the sum of all of its positive divisors.
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The first perfect number is 6, because 1, 2 and 3 are its proper
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positive divisors, and 1 + 2 + 3 = 6. Equivalently, the number 6
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is equal to half the sum of all its positive divisors:
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( 1 + 2 + 3 + 6 ) / 2 = 6.
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*/
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public class IsPerfectNumber
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{
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public boolean isPerfectNumber(int number)
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{
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int temp = 0;
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for(int i=1; i<=number/2; i++)
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{
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if(number%i == 0)
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{
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temp += i;
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}
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}
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if(temp == number)
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{
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System.out.println("It is a perfect number");
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return true;
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}
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else
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{
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System.out.println("It is not a perfect number");
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return false;
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}
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}
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public static void main(String a[])
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{
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IsPerfectNumber ipn = new IsPerfectNumber();
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System.out.println("Is perfect number: "+ipn.isPerfectNumber(28));
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}
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} |