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package org.spongycastle.math.ec;
import java.math.BigInteger;
public class ReferenceMultiplier extends AbstractECMultiplier
{
/**
* Simple shift-and-add multiplication. Serves as reference implementation
* to verify (possibly faster) implementations in
* {@link org.spongycastle.math.ec.ECPoint ECPoint}.
*
* @param p The point to multiply.
* @param k The factor by which to multiply.
* @return The result of the point multiplication <code>k * p</code>.
*/
protected ECPoint multiplyPositive(ECPoint p, BigInteger k)
{
ECPoint q = p.getCurve().getInfinity();
int t = k.bitLength();
if (t > 0)
{
if (k.testBit(0))
{
q = p;
}
for (int i = 1; i < t; i++)
{
p = p.twice();
if (k.testBit(i))
{
q = q.add(p);
}
}
}
return q;
}
}
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