public static integer operator >>(integer x, int shift)
{
if (shift == 0) return x;
else if (shift < 0) return x << -shift;
int digitShift = shift / BitsPerDigit;
int smallShift = shift - (digitShift * BitsPerDigit);
int xl = x.length;
uint[] xd = x.data;
int zl = xl - digitShift;
uint[] zd = new uint[zl];
if (smallShift == 0) {
for (int i = xl - 1; i >= digitShift; i--) {
zd[i - digitShift] = xd[i];
}
} else {
int carryShift = BitsPerDigit - smallShift;
uint carry = 0;
for (int i = xl - 1; i >= digitShift; i--) {
uint rot = xd[i];
zd[i - digitShift] = rot >> smallShift | carry;
carry = rot << carryShift;
}
}
integer result = new integer(x.sign, zd);
if (x.sign < 0 && (x.data[0] & 1) != 0)
result = result - 1;
return result;
}
internal integer modpow(int power, integer mod) {
if (power == 0) return ONE;
if (power < 0) throw new ArgumentOutOfRangeException("power", power, "power must be >= 0");
integer factor = this;
integer result = ONE; //!!! want a mutable here for efficiency
while (power != 0) {
if ((power & 1) != 0) {
result = result * factor;
result = result % mod; //!!! should do all in one step
}
factor = factor.square();
power >>= 1;
}
return result;
}
public static integer lshift(integer x, int shift) {
return x << shift;
}
public static integer rshift(integer x, int shift) {
return x >> shift;
}
public static integer or(integer x, integer y) { return x | y; }
public static integer xor(integer x, integer y) { return x ^ y; }
public static integer divrem(integer x, integer y, out integer mod)
{
integer div;
uint[] q;
uint[] r;
DivModUnsigned(x.data, y.data, out q, out r);
div = new integer(x.sign * y.sign, q);
mod = new integer(x.sign, r);
return div;
}
public static integer and(integer x, integer y) { return x & y; }
public static integer modulo(integer x, integer y) { return x % y; }
public static integer divmod(integer x, integer y, out integer mod)
{
integer div = divrem(x, y, out mod);
if (x.sign != y.sign && mod != ZERO)
{
div = div - 1;
mod = mod + y;
}
return div;
}
public static integer divide(integer x, integer y) { return x / y; }
public static integer multiply(integer x, integer y) { return x * y; }
public static integer subtract(integer x, integer y) { return x - y; }
public static integer add(integer x, integer y) { return x + y; }
public static int Compare(integer x, integer y) {
if (x.sign == y.sign) {
int xl = x.length;
int yl = y.length;
if (xl == yl) {
for (int i = xl - 1; i >= 0; i--) {
if (x.data[i] == y.data[i]) continue;
return x.data[i] > y.data[i] ? x.sign : -x.sign;
}
return 0;
} else {
return xl > yl ? +x.sign : -x.sign;
}
} else {
return x.sign > y.sign ? +1 : -1;
}
}
