Data commit

Task/Pascal-matrix-generation/D/pascal-matrix-generation.d

@@ -0,0 +1,27 @@
+import std.stdio, std.bigint, std.range, std.algorithm;
+
+auto binomialCoeff(in uint n, in uint k) pure nothrow {
+    BigInt result = 1;
+    foreach (immutable i; 1 .. k + 1)
+        result = result * (n - i + 1) / i;
+    return result;
+}
+
+auto pascalUpp(in uint n) pure nothrow {
+    return n.iota.map!(i => n.iota.map!(j => binomialCoeff(j, i)));
+}
+
+auto pascalLow(in uint n) pure nothrow {
+    return n.iota.map!(i => n.iota.map!(j => binomialCoeff(i, j)));
+}
+
+auto pascalSym(in uint n) pure nothrow {
+    return n.iota.map!(i => n.iota.map!(j => binomialCoeff(i + j, i)));
+}
+
+void main() {
+    enum n = 5;
+    writefln("Upper:\n%(%(%2d %)\n%)", pascalUpp(n));
+    writefln("\nLower:\n%(%(%2d %)\n%)", pascalLow(n));
+    writefln("\nSymmetric:\n%(%(%2d %)\n%)", pascalSym(n));
+}