X-Git-Url: https://mattmccutchen.net/bigint/bigint.git/blobdiff_plain/83a639e66e094c683b48215a895f6d35e9d60d32..refs/heads/no-explicit-template-args:/BigUnsigned.cc

diff --git a/BigUnsigned.cc b/BigUnsigned.cc
index a4e6d9b..aa7e691 100644
--- a/BigUnsigned.cc
+++ b/BigUnsigned.cc
@@ -12,12 +12,58 @@ BigUnsigned::BigUnsigned(         long  x) { initFromSignedPrimitive(x); }
 BigUnsigned::BigUnsigned(         int   x) { initFromSignedPrimitive(x); }
 BigUnsigned::BigUnsigned(         short x) { initFromSignedPrimitive(x); }
 
-unsigned long  BigUnsigned::toUnsignedLong () const { return convertToPrimitive      <unsigned long >(); }
-unsigned int   BigUnsigned::toUnsignedInt  () const { return convertToPrimitive      <unsigned int  >(); }
-unsigned short BigUnsigned::toUnsignedShort() const { return convertToPrimitive      <unsigned short>(); }
-long           BigUnsigned::toLong         () const { return convertToSignedPrimitive<         long >(); }
-int            BigUnsigned::toInt          () const { return convertToSignedPrimitive<         int  >(); }
-short          BigUnsigned::toShort        () const { return convertToSignedPrimitive<         short>(); }
+unsigned long  BigUnsigned::toUnsignedLong () const { return convertToPrimitive      ((unsigned long )0); }
+unsigned int   BigUnsigned::toUnsignedInt  () const { return convertToPrimitive      ((unsigned int  )0); }
+unsigned short BigUnsigned::toUnsignedShort() const { return convertToPrimitive      ((unsigned short)0); }
+long           BigUnsigned::toLong         () const { return convertToSignedPrimitive((         long )0); }
+int            BigUnsigned::toInt          () const { return convertToSignedPrimitive((         int  )0); }
+short          BigUnsigned::toShort        () const { return convertToSignedPrimitive((         short)0); }
+
+// BIT/BLOCK ACCESSORS
+
+void BigUnsigned::setBlock(Index i, Blk newBlock) {
+	if (newBlock == 0) {
+		if (i < len) {
+			blk[i] = 0;
+			zapLeadingZeros();
+		}
+		// If i >= len, no effect.
+	} else {
+		if (i >= len) {
+			// The nonzero block extends the number.
+			allocateAndCopy(i+1);
+			// Zero any added blocks that we aren't setting.
+			for (Index j = len; j < i; j++)
+				blk[j] = 0;
+			len = i+1;
+		}
+		blk[i] = newBlock;
+	}
+}
+
+/* Evidently the compiler wants BigUnsigned:: on the return type because, at
+ * that point, it hasn't yet parsed the BigUnsigned:: on the name to get the
+ * proper scope. */
+BigUnsigned::Index BigUnsigned::bitLength() const {
+	if (isZero())
+		return 0;
+	else {
+		Blk leftmostBlock = getBlock(len - 1);
+		Index leftmostBlockLen = 0;
+		while (leftmostBlock != 0) {
+			leftmostBlock >>= 1;
+			leftmostBlockLen++;
+		}
+		return leftmostBlockLen + (len - 1) * N;
+	}
+}
+
+void BigUnsigned::setBit(Index bi, bool newBit) {
+	Index blockI = bi / N;
+	Blk block = getBlock(blockI), mask = 1 << (bi % N);
+	block = newBit ? (block | mask) : (block & ~mask);
+	setBlock(blockI, block);
+}
 
 // COMPARISON
 BigUnsigned::CmpRes BigUnsigned::compareTo(const BigUnsigned &x) const {