Data commit

Task/Increasing-gaps-between-consecutive-Niven-numbers/Delphi/increasing-gaps-between-consecutive-niven-numbers.delphi

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+function SumDigits(N: integer): integer;
+{Sum the integers in a number}
+var T: integer;
+begin
+Result:=0;
+repeat
+	begin
+	T:=N mod 10;
+	N:=N div 10;
+	Result:=Result+T;
+	end
+until N<1;
+end;
+
+
+function IsNiven(N: integer): boolean;
+{Test if N is evenly divisible by sum}
+{i.e. is it a Niven Number}
+var Sum: integer;
+begin
+Sum:=SumDigits(N);
+Result:=(N mod Sum)=0;
+end;
+
+
+function GetNextNiven(Start: integer): integer;
+{Get the next Niven number after Start}
+begin
+repeat Inc(Start)
+until IsNiven(Start);
+Result:=Start;
+end;
+
+
+procedure ShowNivenGaps(Memo: TMemo; Prog: TProgress);
+{Show when gaps between sucessive Niven Numbers changes}
+var I: integer;
+var N1,N2,Gap: integer;
+var Cnt: integer;
+const Limit = 65000000;
+begin
+Memo.Lines.Add('  Gap   Gap          Niven          Niven           Next');
+Memo.Lines.Add('Index Value          Index         Number   Niven Number');
+Memo.Lines.Add('----- -----       --------      ---------   ------------');
+Gap:=0; Cnt:=0;
+N1:=GetNextNiven(0);
+for I:=1 to Limit do
+	begin
+	{Get next Niven and test if Gap has changed}
+	N2:=GetNextNiven(N1);
+	if (N2-N1)>Gap then
+		begin
+		Gap:=N2-N1;
+		Inc(Cnt);
+		Memo.Lines.Add(Format('%5d%6d%15.0n%15.0n%15.0n',[Cnt,Gap,I+0.0,N1+0.0,N2+0.0]));
+		end;
+	N1:=N2;
+	if Assigned(Prog) and ((I mod 100000)=0) then Prog(MulDiv(100,I,Limit));
+	end;
+end;