September 2017 Update

Task/Pascals-triangle/Component-Pascal/pascals-triangle.component

@@ -0,0 +1,71 @@
+MODULE PascalTriangle;
+IMPORT StdLog, DevCommanders, TextMappers;
+
+TYPE
+	Expansion* = POINTER TO ARRAY OF LONGINT;
+
+PROCEDURE Show*(e: Expansion);
+VAR
+	i: INTEGER;
+BEGIN
+	i := 0;
+	WHILE (i < LEN(e)) & (e[i] # 0) DO
+		StdLog.Int(e[i]);
+		INC(i)
+	END;
+	StdLog.Ln
+END Show;
+
+PROCEDURE GenFor*(p: LONGINT): Expansion;
+VAR
+	expA,expB: Expansion;
+	i,j: LONGINT;
+	
+	PROCEDURE Swap(VAR x,y: Expansion);
+	VAR
+		swap: Expansion;
+	BEGIN
+		swap := x; x := y; y := swap
+	END Swap;
+	
+BEGIN
+	ASSERT(p >= 0);
+	NEW(expA,p + 2);NEW(expB,p + 2);
+	FOR i := 0 TO p DO
+		IF i = 0 THEN expA[0] := 1
+		ELSE
+			FOR j := 0 TO i DO
+				IF j = 0 THEN
+					expB[j] := expA[j]
+				ELSE
+					expB[j] := expA[j - 1] + expA[j]
+				END
+			END;
+			Swap(expA,expB)
+		END;
+	END;
+	expB := NIL; (* for the GC *)
+	RETURN expA
+END GenFor;
+
+
+PROCEDURE Do*;
+VAR
+	s: TextMappers.Scanner;
+	exp: Expansion;
+BEGIN
+	s.ConnectTo(DevCommanders.par.text);
+	s.SetPos(DevCommanders.par.beg);
+	s.Scan;
+	WHILE (~s.rider.eot) DO
+		IF (s.type = TextMappers.char) & (s.char = '~') THEN
+			RETURN
+		ELSIF (s.type = TextMappers.int) THEN
+			exp := GenFor(s.int);
+			Show(exp)
+		END;
+		s.Scan
+	END
+END Do;
+
+END PascalTriangle.