Integer _IntMinus(const Integer &a, const Integer &b)
{
Integer exv;
int maxlen = a.size;
if (b.size > maxlen) maxlen = b.size;
exv.assignSpace(maxlen);
int t1, t2;
for (int i = maxlen - 1; i >= 0; --i)
{
if (i >= a.size) t1 = 0; else t1 = a.num[i];
if (i >= b.size) t2 = 0; else t2 = b.num[i];
exv.num[i] = t1 - t2;
int j = i;
while (exv.num[j] < 0)
{
--exv.num[j + 1];
exv.num[j] += 10000;
++j;
}
}
while (exv.size > 1 && exv.num[exv.size - 1] == 0) --exv.size; //delete leading zero
exv.nonnegative = true;
//exv.exactness = a.exactness && b.exactness;
return exv;
}
Integer _IntPlus(const Integer &a, const Integer &b)
{
Integer exv;
int maxlen = a.size;
if (b.size > maxlen) maxlen = b.size; // the longest integer
maxlen += 1;
exv.nonnegative = true;
exv.assignSpace(maxlen);
int t1, t2;
int temp;
for (int i = 0; i < maxlen; ++i)
{
if (i >= a.size) t1 = 0; else t1 = a.num[i];
if (i >= b.size) t2 = 0; else t2 = b.num[i];
temp = exv.num[i] + t1 + t2;
//if (exv.num[i] +)
if (temp >= 10000) ++exv.num[i + 1], temp -= 10000;
if (temp >= 10000) ++exv.num[i + 1], temp -= 10000;
//exv.num[i + 1] += (exv.num[i] + t1 + t2) / 10000; //isopsephy
exv.num[i] = temp;
}
while (exv.size > 1 && exv.num[exv.size - 1] == 0) --exv.size; //delete leading zero
if (exv.size == 1 && exv.num[0] == 0) exv.nonnegative = true;
//exv.exactness = a.exactness && b.exactness;
return exv;
}
Integer IntMult(const Integer &a, const Integer &b)
{
int maxlen = a.size + b.size + 1;
Integer exv;
exv.assignSpace(maxlen);
for (int i = 0; i < a.size; ++i)
for (int j = 0; j < b.size; ++j)
{
exv.num[i + j] = exv.num[i + j] + a.num[i] * b.num[j];
exv.num[i + j + 1] = (exv.num[i + j] / 10000 + exv.num[i + j + 1]);
exv.num[i + j] = exv.num[i + j] % 10000;
}
exv.nonnegative = !(a.nonnegative ^ b.nonnegative);
//exv.exactness = a.exactness && b.exactness;
while (exv.size > 1 && exv.num[exv.size - 1] == 0) --exv.size;
if (exv.size == 1 && exv.num[0] == 0) exv.nonnegative = true;
return exv;
}