Stylistic changes + new math tests

LivInTheLookingGlass · Jul 31, 2024 · 971158a · 971158a
1 parent 16352da
commit 971158a
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Showing 15 changed files with 89 additions and 52 deletions.
diff --git a/csharp/Euler.Test/test.cs b/csharp/Euler.Test/test.cs
@@ -30,11 +30,62 @@ public async Task EulerTest_Problem(Type problem, bool isSlow, object expected)
             if (prob is null)
                 throw new Exception("Unable to construct test object");
             Stopwatch sw = Stopwatch.StartNew();
-            object result = await prob.Answer();
+            object result = await Task.Run(() => prob.Answer());
             sw.Stop();
             Assert.Equal(expected, result);
             if (!isSlow)
                 Assert.True(sw.Elapsed <= oneMinute);
         }
+
+        [Fact]
+        public void EulerTest_Mathematics_Factorial()
+        {
+            List<ulong> results = new() {
+                1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880, 3628800, 39916800, 479001600,6227020800, 87178291200,
+                1307674368000, 20922789888000, 355687428096000, 6402373705728000, 121645100408832000,
+                2432902008176640000
+            };
+            for (byte i = 0; i < results.Count; i += 1)
+            {
+                ulong expected = results[i];
+                Assert.Equal(expected, Mathematics.Factorial(i));
+            }
+        }
+
+        [Fact]
+        public async Task EulerTest_Mathematics_NChooseR()
+        {
+            List<List<ulong>> results = new() {
+                new() { 1, 1 },
+                new() { 1, 2, 1 },
+                new() { 1, 3, 3, 1 },
+                new() { 1, 4, 6, 4, 1 },
+                new() { 1, 5, 10, 10, 5, 1 },
+                new() { 1, 6, 15, 20, 15, 6, 1 },
+                new() { 1, 7, 21, 35, 35, 21, 7, 1 },
+                new() { 1, 8, 28, 56, 70, 56, 28, 8, 1 },
+                new() { 1, 9, 36, 84, 126, 126, 84, 36, 9, 1 },
+                new() { 1, 10, 45, 120, 210, 252, 210, 120, 45, 10, 1 },
+                new() { 1, 11, 55, 165, 330, 462, 462, 330, 165, 55, 11, 1 },
+                new() { 1, 12, 66, 220, 495, 792, 924, 792, 495, 220, 66, 12, 1 },
+                new() { 1, 13, 78, 286, 715, 1287, 1716, 1716, 1287, 715, 286, 78, 13, 1 },
+                new() { 1, 14, 91, 364, 1001, 2002, 3003, 3432, 3003, 2002, 1001, 364, 91, 14, 1 },
+                new() { 1, 15, 105, 455, 1365, 3003, 5005, 6435, 6435, 5005, 3003, 1365, 455, 105, 15, 1 },
+                new() { 1, 16, 120, 560, 1820, 4368, 8008, 11440, 12870, 11440, 8008, 4368, 1820, 560, 120, 16, 1 },
+                new() { 1, 17, 136, 680, 2380, 6188, 12376, 19448, 24310, 24310, 19448, 12376, 6188, 2380, 680, 136, 17, 1 },
+                new() { 1, 18, 153, 816, 3060, 8568, 18564, 21824, 43758, 48620, 43758, 21824, 18564, 8568, 3060, 816, 153, 18, 1 },
+            };
+            List<Task> tasks = new();
+            for (byte i = 0; i < results.Count; i += 1)
+            {
+                for (byte j = 0; j < results[i].Count; j += 1)
+                {
+                    ulong expected = results[i][j];
+                    tasks.Append(Task.Run(() => Assert.Equal(expected, Mathematics.NChooseR(i, j))));
+                }
+            }
+            foreach (Task task in tasks)
+                await task;
+        }
     }
 }
diff --git a/csharp/Euler/include/math.cs b/csharp/Euler/include/math.cs
@@ -7,30 +7,28 @@ public static class Mathematics
         public static ulong Factorial(ulong n)
         {
             ulong answer = 1;
-            for (ulong x = 2; x < n; x += 1)
+            for (ulong x = 2; x <= n; x += 1)
                 answer *= x;
             return answer;
         }
 
         public static ulong NChooseR(ulong n, ulong r)
         {
-            if (n < 20)
+            if (n <= 20)
                 return Factorial(n) / Factorial(r) / Factorial(n - r);
             ulong answer, tmp;
             uint i, j;
             sbyte[] factors = new sbyte[n + 1];
             // collect factors of final number
             for (i = 2; i <= n; i += 1)
                 factors[i] = 1;
+
             // negative factor values indicate need to divide
             for (i = 2; i <= r; i += 1)
-            {
                 factors[i] -= 1;
-            }
             for (i = 2; i <= n - r; i += 1)
-            {
                 factors[i] -= 1;
-            }
+
             // this loop reduces to prime factors only
             for (i = (uint)n; i > 1; i -= 1)
             {
@@ -45,6 +43,7 @@ public static ulong NChooseR(ulong n, ulong r)
                     }
                 }
             }
+
             i = j = 2;
             answer = 1;
             while (i <= n)
@@ -64,13 +63,12 @@ public static ulong NChooseR(ulong n, ulong r)
                         answer = tmp * i;
                     }
                     if (answer < tmp)
-                    {
                         return ulong.MaxValue;  // this indicates an overflow
-                    }
                     factors[i] -= 1;
                 }
                 i += 1;
             }
+
             while (j <= n)
             {
                 while (factors[j] < 0)
@@ -80,6 +78,7 @@ public static ulong NChooseR(ulong n, ulong r)
                 }
                 j += 1;
             }
+
             return answer;
         }
     }

diff --git a/csharp/Euler/p0000_template.cs b/csharp/Euler/p0000_template.cs
@@ -13,13 +13,13 @@ namespace Euler
 {
     public interface IEuler
     {
-        public Task<object> Answer();
+        public object Answer();
     }
     public class p0000 : IEuler
     {
-        public Task<object> Answer()
+        public object Answer()
         {
-            return Task.FromResult<object>(0);
+            return 0;
         }
     }
 }
diff --git a/csharp/Euler/p0001.cs b/csharp/Euler/p0001.cs
@@ -18,7 +18,7 @@ namespace Euler
 {
     public class p0001 : IEuler
     {
-        public Task<object> Answer()
+        public object Answer()
         {
             int answer = 0;
             for (int i = 0; i < 1000; i += 3)
@@ -30,7 +30,7 @@ public Task<object> Answer()
             for (int i = 0; i < 1000; i += 15)
                 answer -= i;
 
-            return Task.FromResult<object>(answer);
+            return answer;
         }
     }
 }
diff --git a/csharp/Euler/p0002.cs b/csharp/Euler/p0002.cs
@@ -20,7 +20,7 @@ namespace Euler
 {
     public class p0002 : IEuler
     {
-        public Task<object> Answer()
+        public object Answer()
         {
             int answer = 0,
                   i = 2,
@@ -35,7 +35,7 @@ public Task<object> Answer()
                 j = tmp;
             }
 
-            return Task.FromResult<object>(answer);
+            return answer;
         }
     }
 }
diff --git a/csharp/Euler/p0004.cs b/csharp/Euler/p0004.cs
@@ -31,7 +31,7 @@ private static bool IsPalindrome(int x)
             return rep == Reverse(rep);
         }
 
-        public Task<object> Answer()
+        public object Answer()
         {
             int answer = 0;
             for (int v = 101; v < 1000; v++)
@@ -40,13 +40,11 @@ public Task<object> Answer()
                 {
                     int p = u * v;
                     if (IsPalindrome(p) && p > answer)
-                    {
                         answer = p;
-                    }
                 }
             }
 
-            return Task.FromResult<object>(answer);
+            return answer;
         }
     }
 }
diff --git a/csharp/Euler/p0006.cs b/csharp/Euler/p0006.cs
@@ -23,7 +23,7 @@ namespace Euler
 {
     public class p0006 : IEuler
     {
-        public Task<object> Answer()
+        public object Answer()
         {
             int sum_of_squares = 0,
                   sum = 0;
@@ -32,8 +32,9 @@ public Task<object> Answer()
                 sum += i;
                 sum_of_squares += i * i;
             }
+
             int square_of_sum = sum * sum;
-            return Task.FromResult<object>(square_of_sum - sum_of_squares);
+            return square_of_sum - sum_of_squares;
         }
     }
 }
diff --git a/csharp/Euler/p0008.cs b/csharp/Euler/p0008.cs
@@ -40,7 +40,7 @@ namespace Euler
     public class p0008 : IEuler
     {
         private const int MAX = 500;
-        public Task<object> Answer()
+        public object Answer()
         {
             String str = String.Concat(
                 "73167176531330624919225119674426574742355349194934",
@@ -70,15 +70,12 @@ public Task<object> Answer()
                 String slice = str.Substring(i, 13);
                 Int64 prod = 1;
                 foreach (char c in slice)
-                {
                     prod *= c - '0';
-                }
+
                 if (prod > answer)
-                {
                     answer = prod;
-                }
             }
-            return Task.FromResult<object>(answer);
+            return answer;
         }
     }
 }
diff --git a/csharp/Euler/p0009.cs b/csharp/Euler/p0009.cs
@@ -19,7 +19,7 @@ namespace Euler
 {
     public class p0009 : IEuler
     {
-        public Task<object> Answer()
+        public object Answer()
         {
             for (int c = 3; ; c++)
             {
@@ -31,9 +31,7 @@ public Task<object> Answer()
                     {
                         int a_square = a * a;
                         if (a_square + b_square == c_square && a + b + c == 1000)
-                        {
-                            return Task.FromResult<object>(a * b * c);
-                        }
+                            return a * b * c;
                     }
                 }
             }

diff --git a/csharp/Euler/p0011.cs b/csharp/Euler/p0011.cs
@@ -23,7 +23,7 @@ namespace Euler
 {
     public class p0011 : IEuler
     {
-        public Task<object> Answer()
+        public object Answer()
         {
             int answer = 0, tmp;
             for (byte i = 0; i < 20; i++)
@@ -50,7 +50,7 @@ public Task<object> Answer()
                     answer = Math.Max(answer, tmp);
                 }
             }
-            return Task.FromResult<object>(answer);
+            return answer;
         }
 
         byte[][] grid = new byte[20][]{

diff --git a/csharp/Euler/p0014.cs b/csharp/Euler/p0014.cs
@@ -26,7 +26,7 @@ namespace Euler
 {
     public class p0014 : IEuler
     {
-        public Task<object> Answer()
+        public object Answer()
         {
             int biggestSeen = 0;
             long biggestIdx = 0;
@@ -40,28 +40,21 @@ public Task<object> Answer()
                     biggestIdx = x;
                 }
             }
-            return Task.FromResult<object>((int)biggestIdx);
+            return (int)biggestIdx;
         }
 
         static int CollatzLen(long n, IDictionary<long, int> cache)
         {
             if (n == 1)
-            {
                 return 0;
-            }
             else if (cache.ContainsKey(n))
-            {
                 return cache[n];
-            }
+
             int result;
             if (n % 2 == 0)
-            {
                 result = 1 + CollatzLen(n / 2, cache);
-            }
             else
-            {
                 result = 2 + CollatzLen((3 * n + 1) / 2, cache);
-            }
             cache.Add(n, result);
             return result;
         }

diff --git a/csharp/Euler/p0015.cs b/csharp/Euler/p0015.cs
@@ -20,9 +20,9 @@ namespace Euler
 {
     public class p0015 : IEuler
     {
-        public Task<object> Answer()
+        public object Answer()
         {
-            return Task.FromResult<object>((long)Mathematics.NChooseR(40, 20));
+            return (long)Mathematics.NChooseR(40, 20);
         }
     }
 }
diff --git a/csharp/Euler/p0017.cs b/csharp/Euler/p0017.cs
@@ -23,15 +23,15 @@ namespace Euler
 {
     public class p0017 : IEuler
     {
-        public Task<object> Answer()
+        public object Answer()
         {
             int answer = 0;
             for (int x = 1; x < 1001; x += 1)
             {
                 string str = to_string(x);
                 answer += str.Replace(" ", "").Replace("-", "").Length;
             }
-            return Task.FromResult<object>(answer);
+            return answer;
         }
 
         static String to_string(int n)

diff --git a/csharp/Euler/p0076.cs b/csharp/Euler/p0076.cs
@@ -24,7 +24,7 @@ namespace Euler
 {
     public class p0076 : IEuler
     {
-        public Task<object> Answer()
+        public object Answer()
         {
             ushort idx;
             int answer = 0;
@@ -54,7 +54,7 @@ public Task<object> Answer()
                 }
                 sum = Enumerable.Sum(counts);
             }
-            return Task.FromResult<object>(answer);
+            return answer;
         }
     }
 }
diff --git a/csharp/Euler/p0836.cs b/csharp/Euler/p0836.cs
@@ -20,9 +20,9 @@ namespace Euler
 {
     public class p0836 : IEuler
     {
-        public Task<object> Answer()
+        public object Answer()
         {
-            return Task.FromResult<object>("aprilfoolsjoke");
+            return "aprilfoolsjoke";
         }
     }
 }