uint160 and uint256 division operations.

[NovacoinLibrary.git] / Novacoin / uint256.cs

diff --git a/Novacoin/uint256.cs b/Novacoin/uint256.cs
index 60e570d..606acf0 100644 (file)
--- a/Novacoin/uint256.cs
+++ b/Novacoin/uint256.cs
@@ -18,6 +18,7 @@
 
 using System;
 using System.Diagnostics.Contracts;
+using System.Linq;
 
 namespace Novacoin
 {
@@ -268,6 +269,83 @@ namespace Novacoin
 
             return result;
         }
+
+        public static uint256 operator *(uint256 a, uint b)
+        {
+            var result = new uint256();
+
+            ulong c = 0;
+            uint i = 0;
+
+            do
+            {
+                c += a.pn[i] * (ulong)b;
+                result.pn[i] = (uint)c;
+                c >>= 32;
+            } while (++i < result.nWidth);
+
+            return result;
+        }
+
+        public static uint operator %(uint256 a, uint b)
+        {
+            ulong r = 0;
+            int i = a.nWidth;
+
+            while (i-- > 0)
+            {
+                r <<= 32;
+                r |= a.pn[i];
+                r %= b;
+            }
+
+            return (uint)r;
+        }
+
+        public static uint256 operator /(uint256 a, uint256 b)
+        {
+            if (b.bits <= 32)
+            {
+                return a / b.Low32;
+            }
+
+            uint256 result = new uint256();
+
+            uint[] quotient;
+            uint[] remainder_value;
+
+            int m = a.bits / 32 + (a.bits % 32 != 0 ? 1 : 0);
+            int n = b.bits / 32 + (b.bits % 32 != 0 ? 1 : 0);
+
+            BignumHelper.DivModUnsigned(a.pn.Take(m).ToArray(), b.pn.Take(n).ToArray(), out quotient, out remainder_value);
+
+            quotient.CopyTo(result.pn, 0);
+
+            return result;
+        }
+
+        public static uint256 operator %(uint256 a, uint256 b)
+        {
+            if (b.bits <= 32)
+            {
+                return a % b.Low32;
+            }
+
+            uint256 result = new uint256();
+
+            uint[] quotient;
+            uint[] remainder_value;
+
+            int m = a.bits / 32 + (a.bits % 32 != 0 ? 1 : 0);
+            int n = b.bits / 32 + (b.bits % 32 != 0 ? 1 : 0);
+
+            BignumHelper.DivModUnsigned(a.pn.Take(m).ToArray(), b.pn.Take(n).ToArray(), out quotient, out remainder_value);
+
+            remainder_value.CopyTo(result.pn, 0);
+
+            return result;
+
+        }
         #endregion
 
         #region Shift