ECFieldElementFp.prototype.getR = function() {
if (this.r != undefined) return this.r;
this.r = null;
var bitLength = this.q.bitLength();
if (bitLength > 128) {
var firstWord = this.q.shiftRight(bitLength - 64);
if (firstWord.intValue() == -1) {
this.r = BigInteger.ONE.shiftLeft(bitLength).subtract(this.q);
}
}
return this.r;
};
ECFieldElementFp.prototype.lucasSequence = function(P, Q, k) {
var n = k.bitLength();
var s = k.getLowestSetBit();
var Uh = BigInteger.ONE;
var Vl = BigInteger.ONE.add(BigInteger.ONE);
var Vh = P;
var Ql = BigInteger.ONE;
var Qh = BigInteger.ONE;
for (var j = n - 1; j >= s + 1; --j) {
Ql = this.modMult(Ql, Qh);
if (k.testBit(j)) {
Qh = this.modMult(Ql, Q);
Uh = this.modMult(Uh, Vh);
Vl = this.modReduce(Vh.multiply(Vl).subtract(P.multiply(Ql)));
Vh = this.modReduce(Vh.multiply(Vh).subtract(Qh.shiftLeft(1)));
} else {
Qh = Ql;
Uh = this.modReduce(Uh.multiply(Vl).subtract(Ql));
Vh = this.modReduce(Vh.multiply(Vl).subtract(P.multiply(Ql)));
Vl = this.modReduce(Vl.multiply(Vl).subtract(Ql.shiftLeft(1)));
}
}
Ql = this.modMult(Ql, Qh);
Qh = this.modMult(Ql, Q);
Uh = this.modReduce(Uh.multiply(Vl).subtract(Ql));
Vl = this.modReduce(Vh.multiply(Vl).subtract(P.multiply(Ql)));
Ql = this.modMult(Ql, Qh);
for (var j = 1; j <= s; ++j) {
Uh = this.modMult(Uh, Vl);
Vl = this.modReduce(Vl.multiply(Vl).subtract(Ql.shiftLeft(1)));
Ql = this.modMult(Ql, Ql);
}
return [Uh, Vl];
};