第５話の最後に示したコードではだめであるな理由を説明しましょう。
はじめの値１
合計上限値１００
変化の幅１
の場合で考えます。
１＋２＋３＋・・・＋１３＝９１です。
'１乗の和の計算
Sub f1(h As Long, o As Long, b As Long)
Dim i As Long, w As Long
w = 0
i = h
Do While w < o
w = w + i
i = i + b
Loop
Cells(9, 4) = w
End Sub
これはまだ、w < oを満たしていますから、次の計算
９１＋１４が行われてしまいます。
したがって、和は１０５になって１００を超えてしまいます。
だから、条件式では次の１４を加えたときに、超えないかを判断しなければなりませんので、
w + i <= oとしなければなりません。
While文による解答例
Private Sub CommandButton1_Click()
Dim h As Long, o As Long, b As Long
h = Cells(5, 2)
o = Cells(6, 2)
b = Cells(7, 2)
f1 h, o, b '１乗の和の計算
f2 h, o, b '２乗の和の計算
f3 h, o, b '３乗の和の計算
f4 h, o, b '４乗の和の計算
End Sub
'１乗の和の計算
Sub f1(h As Long, o As Long, b As Long)
Dim i As Long, w As Long
w = 0
i = h
While w + i <= o
w = w + i
i = i + b
Wend
Cells(9, 4) = w
End Sub
'２乗の和の計算
Sub f2(h As Long, o As Long, b As Long)
Dim i As Long, w As Long
w = 0
i = h
While w + i * i <= o
w = w + i * i
i = i + b
Wend
Cells(10, 4) = w
End Sub
'３乗の和の計算
Sub f3(h As Long, o As Long, b As Long)
Dim i As Long, w As Long
w = 0
i = h
While w +i * i * i <= o
w = w + i * i * i
i = i + b
Wend
Cells(11, 4) = w
End Sub
'４乗の和の計算
Sub f4(h As Long, o As Long, b As Long)
Dim i As Long, w As Long
w = 0
i = h
While w + i * i * i * i <= o
w = w + i * i * i * i
i = i + b
Wend
Cells(12, 4) = w
End Sub
Private Sub CommandButton2_Click()
Range("B5:B7,D9:D13").Select
Selection.ClearContents
Cells(1, 1).Select
End Sub
Do...Loop Until文による解答例
Private Sub CommandButton1_Click()
Dim h As Long, o As Long, b As Long
h = Cells(5, 2)
o = Cells(6, 2)
b = Cells(7, 2)
f1 h, o, b '１乗の和の計算
f2 h, o, b '２乗の和の計算
f3 h, o, b '３乗の和の計算
f4 h, o, b '４乗の和の計算
End Sub
'１乗の和の計算
Sub f1(h As Long, o As Long, b As Long)
Dim i As Long, w As Long
w = 0
i = h
Do
w = w + i
i = i + b
Loop Until w + i > o
Cells(9, 4) = w
End Sub
'２乗の和の計算
Sub f2(h As Long, o As Long, b As Long)
Dim i As Long, w As Long
w = 0
i = h
Do
w = w + i * i
i = i + b
Loop Until w + i * i > o
Cells(10, 4) = w
End Sub
'３乗の和の計算
Sub f3(h As Long, o As Long, b As Long)
Dim i As Long, w As Long
w = 0
i = h
Do
w = w + i * i * i
i = i + b
Loop Until w + i * i * i > o
Cells(11, 4) = w
End Sub
'４乗の和の計算
Sub f4(h As Long, o As Long, b As Long)
Dim i As Long, w As Long
w = 0
i = h
Do
w = w + i * i * i * i
i = i + b
Loop Until w + i * i * i * i> o
Cells(12, 4) = w
End Sub
Do While...Loop文、Do...While Loop文、Do Until...Loop文については解答例を省略させていただきます。
次話では、While文とFor文の関係を考えてみたいと思いますので、
合計上限値を超えない範囲で和を計算させるという課題をFor文で成就させましょう。
第５話へ 第７話へ
