static public Ep MsgToEp(BigInteger m)
{
BigInteger z;
for (int index = 0; index < 100; index++)
{
BigInteger x = (100 * m) + index;
z = x ^ 3 + ECC._a * x + ECC._b;
if (IntegerCalclator.LegendreSymbol(z, ECC._p))
{
BigInteger y = IntegerCalclator.SqrtMod(z, ECC._p);
return(new Ep(x, y));
}
}
//エラー
return(new Ep());
}
//コンストラスタ：初期位置を入力
public Ep(BigInteger m)
{
BigInteger z;
BigInteger y = 0;
BigInteger x = 0;
for (int index = 0; index < 100; index++)
{
x = (100 * m) + index;
z = (x ^ 3) + (ECC.a * x) + ECC.b; //z=y^2に注意
if (IntegerCalclator.LegendreSymbol(z, ECC.p))
{
y = IntegerCalclator.SqrtMod(z, ECC.p);
break;
}
}
this.x = x;
this.y = y;
}
//平方剰余計算テスト
public void SqrtModTest()
{
Console.Write("a= ");
string strA = Console.ReadLine();
BigInteger a = BigInteger.Parse(strA);
Console.Write("p= ");
string strP = Console.ReadLine();
BigInteger p = BigInteger.Parse(strP);
if (IntegerCalclator.LegendreSymbol(a, p))
{
BigInteger x = IntegerCalclator.SqrtMod(a, p);
Console.Write("Answer: ");
Console.WriteLine(x.ToString());
}
else
{
Console.WriteLine("aはpの倍数か平方非剰余です");
}
}