/// <summary>
/// 按位乘法运算（不考虑正负号）
/// </summary>
/// <param name="num">乘数</param>
/// <param name="maxDecimalPlaces">答案保留小数位数</param>
/// <returns></returns>
protected override Digitable Multiply_unsigned(Digitable num, int maxDecimalPlaces)
{
NumStr a = this, b = num as NumStr;
if (a == null || b == null)
{
throw new ProgramInterruptException(ProgramInterruptExceptionType.IllegalValue);
}
//统一计算空间
if (a.Space != b.Space)
{
if (a.Space == OperationSpace.DefaultSpace)
{
a = (NumStr)a.ChangeOperationSpace(b.Space);
}
else if (b.Space == OperationSpace.DefaultSpace)
{
b = (NumStr)b.ChangeOperationSpace(a.Space);
}
else
{
throw new ProgramInterruptException(ProgramInterruptExceptionType.NotSameOperationSpace);
}
}
var ans = new NumStr(0, a.Space, maxDecimalPlaces);
//特殊情况
if (a.IsZero || b.IsZero)
{
return(ans);
}
var ansDecimalPlaces = a.DecimalPlaces + b.DecimalPlaces;
//更换乘数
if (a.integerNumList == null && a.decimalNumList?.First.Value == 0)
{
a = a.RemoveDecimalPoint();
}
if (b.integerNumList == null && b.decimalNumList?.First.Value == 0)
{
b = b.RemoveDecimalPoint();
}
long remain = 0;
var maxAnsPlaces = DefaultSettings.MaxIntegerPlaces + ansDecimalPlaces;
var tmpList = new LinkedList <uint>(); //缓存链
var ptrHead = tmpList.First;
var ptr = tmpList.First;
foreach (var bi in b)
{
if (ptrHead == null)
{
tmpList.AddLast(0);
if (tmpList.Count > maxAnsPlaces)
{
throw new NumberOutOfRangeException();
}
ptrHead = tmpList.Last;
}
ptr = ptrHead;
if (bi > 0)
{
foreach (var ai in a)
{
var product = ai * bi + remain;
remain = product / ans.NumberBase;
product %= ans.NumberBase;
if (ptr == null)
{
tmpList.AddLast((uint)product);
if (tmpList.Count > maxAnsPlaces)
{
throw new NumberOutOfRangeException();
}
ptr = tmpList.Last;
}
else
{
ptr.Value += (uint)product;
}
ptr = ptr.Next;
}
if (remain > 0)
{
if (ptr == null)
{
tmpList.AddLast((uint)remain);
if (tmpList.Count > maxAnsPlaces)
{
throw new NumberOutOfRangeException();
}
}
else
{
ptr.Value += (uint)remain;
}
remain = 0;
}
}
ptrHead = ptrHead.Next;
}
//依次进位
remain = 0;
ptr = tmpList.First;
while (ptr != null)
{
ptr.Value += (uint)remain;
if (ptr.Value >= ans.NumberBase)
{
remain = ptr.Value / ans.NumberBase;
ptr.Value %= ans.NumberBase;
}
else
{
remain = 0;
}
ptr = ptr.Next;
}
if (remain > 0)
{
tmpList.AddLast((uint)remain);
if (tmpList.Count > maxAnsPlaces)
{
throw new NumberOutOfRangeException();
}
}
//录入答案
ptr = tmpList.First;
//调整光标位置
var tmpn = Math.Max(0, (long)ansDecimalPlaces - (long)maxDecimalPlaces);
for (int i = 0; i < tmpn; i++)
{
ptr = ptr.Next;
}
var DecimalPlaces = Math.Min(ansDecimalPlaces, maxDecimalPlaces);
bool flag = true; //判断小数位最高位是否为0
for (int i = 0; i < DecimalPlaces; i++)
{
if (ptr == null)
{
ans.decimalNumList.AddFirst(0);
}
else
{
if (ptr.Value > 0 || !flag)
{
if (flag)
{
flag = false;
ans.decimalNumList = new LinkedList <uint>();
}
ans.decimalNumList.AddFirst(ptr.Value);
}
ptr = ptr.Next;
}
}
if (ptr != null)
{
ans.integerNumList = new LinkedList <uint>();
do
{
ans.integerNumList.AddLast(ptr.Value);
ptr = ptr.Next;
}while (ptr != null);
}
return(ans);
}
/// <summary>
/// 按位除法运算（不考虑正负号）
/// </summary>
/// <param name="num">除数</param>
/// <param name="maxDecimalPlaces">答案保留小数位数</param>
/// <returns></returns>
protected override Digitable Divide_unsigned(Digitable num, int maxDecimalPlaces)
{
NumStr a = this, b = num as NumStr;
//方法：手动模拟法 + 二分查找优化
if (a == null || b == null)
{
throw new ProgramInterruptException(ProgramInterruptExceptionType.IllegalValue);
}
//统一计算空间
if (a.Space != b.Space)
{
if (a.Space == OperationSpace.DefaultSpace)
{
a = (NumStr)a.ChangeOperationSpace(b.Space);
}
else if (b.Space == OperationSpace.DefaultSpace)
{
b = (NumStr)b.ChangeOperationSpace(a.Space);
}
else
{
throw new ProgramInterruptException(ProgramInterruptExceptionType.NotSameOperationSpace);
}
}
var ans = new NumStr(0, a.Space, maxDecimalPlaces);
//特殊情况
if (a.IsZero)
{
return(ans);
}
else if (b.IsZero)
{
throw new IllegalOperationException(IllegalOperationExceptionType.DivideByZero);
}
int a_ptr = 0;
var a_integerPlaces = a.IntegerPlaces + b.DecimalPlaces; //被除数的小数点位置
if (b.decimalNumList != null)
{
b = b.RemoveDecimalPoint();
}
var an = a.IntegerPlaces + a.DecimalPlaces;
var bn = b.IntegerPlaces;
var new_a = new NumStr(0, a.Space, 0); //被除数片段
var b_table = new NumStr[ans.NumberBase]; //除数的倍数表
var aii = a.GetInverseEnumerator();
var bii = b.GetInverseEnumerator();
bool?a_less_than_b = null;
LinkedListNode <uint> node_ptr = null;
while (true)
{
//补位
bii = b.GetInverseEnumerator();
a_less_than_b = null;
if (new_a.IsPositive)
{
var aii2 = new_a.GetInverseEnumerator();
while (a_less_than_b == null && aii2.MoveNext() && bii.MoveNext())
{
if (aii2.Current < bii.Current)
{
a_less_than_b = true;
}
else if (aii2.Current > bii.Current)
{
a_less_than_b = false;
}
}
}
do
{
var v = aii.MoveNext() ? aii.Current : 0;
if (v > 0 || new_a.IsPositive)
{
if (new_a.IsZero)
{
new_a.PositiveOrNegative = 1;
new_a.integerNumList = new LinkedList <uint>();
}
new_a.integerNumList.AddFirst(v);
bii.MoveNext();
if (a_less_than_b == null)
{
if (v < bii.Current)
{
a_less_than_b = true;
}
else if (v > bii.Current)
{
a_less_than_b = false;
}
}
}
a_ptr++;
if (a_ptr <= a_integerPlaces)
{
if (ans.IsZero)
{
ans.PositiveOrNegative = 1;
ans.integerNumList = new LinkedList <uint>();
}
if (ans.IntegerPlaces != 1 || ans.integerNumList.Last.Value > 0)
{
ans.integerNumList.AddFirst(0);
if (ans.IntegerPlaces > DefaultSettings.MaxIntegerPlaces)
{
throw new NumberOutOfRangeException();
}
node_ptr = ans.integerNumList.First;
}
}
else
{
if (ans.DecimalPlaces == maxDecimalPlaces)
{
return(ans);
}
if (ans.decimalNumList == null)
{
ans.decimalNumList = new LinkedList <uint>();
}
ans.decimalNumList.AddLast(0);
node_ptr = ans.decimalNumList.Last;
}
} while (new_a.IntegerPlaces < bn + (a_less_than_b == true ? 1 : 0));
//做整除
var quotient = Divide_unsigned_b_table_binary_search(b_table, b, new_a);
if (node_ptr != null)
{
node_ptr.Value = quotient;
node_ptr = null;
}
else
{
if (a_ptr <= a_integerPlaces)
{
if (ans.integerNumList == null)
{
ans.integerNumList = new LinkedList <uint>();
}
ans.integerNumList.AddFirst(quotient);
if (ans.IntegerPlaces > DefaultSettings.MaxIntegerPlaces)
{
throw new NumberOutOfRangeException();
}
}
else
{
if (ans.decimalNumList == null)
{
ans.decimalNumList = new LinkedList <uint>();
}
ans.decimalNumList.AddLast(quotient);
}
}
if (maxDecimalPlaces > 0 && ans.DecimalPlaces >= maxDecimalPlaces)
{
return(ans);
}
//求余
new_a = new_a - b_table[quotient];
if (new_a.IsZero && a_ptr >= an)
{
return(ans);
}
}
}