X-Git-Url: https://mattmccutchen.net/bigint/bigint.git/blobdiff_plain/83a639e66e094c683b48215a895f6d35e9d60d32..cb2f0c288d4b7acfa37d7a9c8bc1024c3f332b5f:/BigUnsigned.hh

diff --git a/BigUnsigned.hh b/BigUnsigned.hh
index 0813234..683ac8b 100644
--- a/BigUnsigned.hh
+++ b/BigUnsigned.hh
@@ -81,7 +81,7 @@ protected:
 	template <class X> X convertToPrimitive      () const;
 public:
 
-	// ACCESSORS
+	// BIT/BLOCK ACCESSORS
 
 	// Expose these from NumberlikeArray directly.
 	NumberlikeArray<Blk>::getCapacity;
@@ -90,10 +90,25 @@ public:
 	/* Returns the requested block, or 0 if it is beyond the length (as if
 	 * the number had 0s infinitely to the left). */
 	Blk getBlock(Index i) const { return i >= len ? 0 : blk[i]; }
+	/* Sets the requested block.  The number grows or shrinks as necessary. */
+	void setBlock(Index i, Blk newBlock);
 
 	// The number is zero if and only if the canonical length is zero.
 	bool isZero() const { return NumberlikeArray<Blk>::isEmpty(); }
 
+	/* Returns the length of the number in bits, i.e., zero if the number
+	 * is zero and otherwise one more than the largest value of bi for
+	 * which getBit(bi) returns true. */
+	Index bitLength() const;
+	/* Get the state of bit bi, which has value 2^bi.  Bits beyond the
+	 * number's length are considered to be 0. */
+	bool getBit(Index bi) const {
+		return (getBlock(bi / N) & (1 << (bi % N))) != 0;
+	}
+	/* Sets the state of bit bi to newBit.  The number grows or shrinks as
+	 * necessary. */
+	void setBit(Index bi, bool newBit);
+
 	// COMPARISONS
 
 	// Compares this to x like Perl's <=>
@@ -326,7 +341,7 @@ inline void BigUnsigned::operator >>=(int b) {
 
 /* Templates for conversions of BigUnsigned to and from primitive integers.
  * BigInteger.cc needs to instantiate convertToPrimitive, and the uses in
- * BigUnsigned.cc didn't do the trick; I think gcc inlined convertToPrimitive
+ * BigUnsigned.cc didn't do the trick; I think g++ inlined convertToPrimitive
  * instead of generating linkable instantiations.  So for consistency, I put
  * all the templates here. */