-/*
-* Matt McCutchen's Big Integer Library
-*/
+#include "BigUnsignedInABase.hh"
-/*
-* Milan Tomic had trouble compiling this file on Microsoft
-* Visual C++ 6 because, in the libraries that come with
-* Visual C++ 6, the `std::string::push_back' method apparently
-* does not exist. To get around the problem, I rewrote
-* `BigUnsignedInABase::operator std::string' (at the bottom
-* of this file) so it doesn't use `push_back'.
-*/
+BigUnsignedInABase::BigUnsignedInABase(const Digit *d, Index l, Base base)
+ : NumberlikeArray<Digit>(d, l), base(base) {
+ // Check the base
+ if (base < 2)
+ throw "BigUnsignedInABase::BigUnsignedInABase(const Digit *, Index, Base): The base must be at least 2";
-#include "BigUnsignedInABase.hh"
+ // Validate the digits.
+ for (Index i = 0; i < l; i++)
+ if (blk[i] >= base)
+ throw "BigUnsignedInABase::BigUnsignedInABase(const Digit *, Index, Base): A digit is too large for the specified base";
+
+ // Eliminate any leading zeros we may have been passed.
+ zapLeadingZeros();
+}
namespace {
unsigned int bitLen(unsigned int x) {
}
BigUnsignedInABase::BigUnsignedInABase(const BigUnsigned &x, Base base) {
-
// Check the base
if (base < 2)
throw "BigUnsignedInABase(BigUnsigned, Base): The base must be at least 2";
- // Save the base.
- // This pattern is seldom seen in C++, but the analogous ``this.'' is common in Java.
this->base = base;
-
+
// Get an upper bound on how much space we need
int maxBitLenOfX = x.getLength() * BigUnsigned::N;
int minBitsPerDigit = bitLen(base) - 1;
int maxDigitLenOfX = ceilingDiv(maxBitLenOfX, minBitsPerDigit);
- len = maxDigitLenOfX; // Another change to comply with `staying in bounds'; see `BigUnsigned::divideWithRemainder'.
+ len = maxDigitLenOfX; // Another change to comply with `staying in bounds'.
allocate(len); // Get the space
-
+
BigUnsigned x2(x), buBase(base);
Index digitNum = 0;
-
+
while (!x2.isZero()) {
// Get last digit. This is like `lastDigit = x2 % buBase, x2 /= buBase'.
BigUnsigned lastDigit(x2);
lastDigit.divideWithRemainder(buBase, x2);
// Save the digit.
- blk[digitNum] = Digit(lastDigit); // invokes `BigUnsigned ==> unsigned short' converter
+ blk[digitNum] = lastDigit.toUnsignedShort();
// Move on. We can't run out of room: we figured it out above.
digitNum++;
}
-
+
// Save the actual length.
len = digitNum;
}
// Save the base.
// This pattern is seldom seen in C++, but the analogous ``this.'' is common in Java.
this->base = base;
-
+
// `s.length()' is a `size_t', while `len' is a `NumberlikeArray::Index',
// also known as an `unsigned int'. Some compilers warn without this cast.
len = Index(s.length());
allocate(len);
-
+
Index digitNum, symbolNumInString;
for (digitNum = 0; digitNum < len; digitNum++) {
symbolNumInString = len - 1 - digitNum;
blk[digitNum] = theSymbol - 'a' + 10;
else
throw "BigUnsignedInABase(std::string, Base): Bad symbol in input. Only 0-9, A-Z, a-z are accepted.";
+
+ if (blk[digitNum] >= base)
+ throw "BigUnsignedInABase::BigUnsignedInABase(const Digit *, Index, Base): A digit is too large for the specified base";
}
zapLeadingZeros();
}
throw "BigUnsignedInABase ==> std::string: The default string conversion routines use the symbol set 0-9, A-Z and therefore support only up to base 36. You tried a conversion with a base over 36; write your own string conversion routine.";
if (len == 0)
return std::string("0");
+ // Some compilers don't have push_back, so use a char * buffer instead.
char *s = new char[len + 1];
s[len] = '\0';
Index digitNum, symbolNumInString;
s[symbolNumInString] = char('A' + theDigit - 10);
}
std::string s2(s);
- delete s;
+ delete [] s;
return s2;
}