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-rw-r--r--bigint/BigUnsignedInABase.cc125
1 files changed, 0 insertions, 125 deletions
diff --git a/bigint/BigUnsignedInABase.cc b/bigint/BigUnsignedInABase.cc
deleted file mode 100644
index 999faaf2..00000000
--- a/bigint/BigUnsignedInABase.cc
+++ /dev/null
@@ -1,125 +0,0 @@
-#include "BigUnsignedInABase.hh"
-
-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";
-
- // 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) {
- unsigned int len = 0;
- while (x > 0) {
- x >>= 1;
- len++;
- }
- return len;
- }
- unsigned int ceilingDiv(unsigned int a, unsigned int b) {
- return (a + b - 1) / b;
- }
-}
-
-BigUnsignedInABase::BigUnsignedInABase(const BigUnsigned &x, Base base) {
- // Check the base
- if (base < 2)
- throw "BigUnsignedInABase(BigUnsigned, Base): The base must be at least 2";
- 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'.
- 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] = lastDigit.toUnsignedShort();
- // Move on. We can't run out of room: we figured it out above.
- digitNum++;
- }
-
- // Save the actual length.
- len = digitNum;
-}
-
-BigUnsignedInABase::operator BigUnsigned() const {
- BigUnsigned ans(0), buBase(base), temp;
- Index digitNum = len;
- while (digitNum > 0) {
- digitNum--;
- temp.multiply(ans, buBase);
- ans.add(temp, BigUnsigned(blk[digitNum]));
- }
- return ans;
-}
-
-BigUnsignedInABase::BigUnsignedInABase(const std::string &s, Base base) {
- // Check the base.
- if (base > 36)
- throw "BigUnsignedInABase(std::string, Base): 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.";
- // 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;
- char theSymbol = s[symbolNumInString];
- if (theSymbol >= '0' && theSymbol <= '9')
- blk[digitNum] = theSymbol - '0';
- else if (theSymbol >= 'A' && theSymbol <= 'Z')
- blk[digitNum] = theSymbol - 'A' + 10;
- else if (theSymbol >= 'a' && theSymbol <= 'z')
- 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();
-}
-
-BigUnsignedInABase::operator std::string() const {
- if (base > 36)
- 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;
- for (symbolNumInString = 0; symbolNumInString < len; symbolNumInString++) {
- digitNum = len - 1 - symbolNumInString;
- Digit theDigit = blk[digitNum];
- if (theDigit < 10)
- s[symbolNumInString] = char('0' + theDigit);
- else
- s[symbolNumInString] = char('A' + theDigit - 10);
- }
- std::string s2(s);
- delete [] s;
- return s2;
-}