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Message:

amicable

Posted by tricky on February 09, 2002 at 8:25 AM

simple method :
first you need a function as you mentioned it which returns the sum of divisors when a integer n is given,
e.g. with two functions

public boolean divides (int n, int m)
{
if (m%n>0) {return false;}
else return true;
}

making use of "%" modulo which gives the rest of m divided by n.Here and in the following there could some grammatical(concerning Java) mistakes, but you said you needed the basic idea.

next function
gives the sum of divisors of n

public int sumdiv (int n)
{
int sum=0;
for (i=2;i{
if (divides(n,i)) // making use of the upper function
{
sum=+i;
}
}
return sum;
}

Using these functions
we should answer : Is n amicable ?

public boolean amicable(int n)
{
int m=sumdiv(n);
if (sumdiv(m)==n) return true;
else return false;
}

Added to a "for (..).." in the main method this should do the job.
If you want to write the programm you should create a class.

public class number
{
static int number;
int sum; // sum of all divisors
boolean amicable;
// methods (see above)

}

i hope i could help you