Циклические алгоритмы

'Заполняем матрицу генератором случ.чисел  [-50;50] целыми
Public Sub diagonal()
Dim a(1 To 5, 1 To 5) As Integer
Dim sum As Integer, i, j
sum = 0
For i = 1 To 5
For j = 1 To 5
a(i, j) = Int((100) * Rnd - 50)
Cells(i, j) = a(i, j)   'Выводим на лист 
Next j
sum = sum + a(i, i)  'Считаем элементы главной диагонали
Next i
MsgBox sum
End Sub

Public Sub diagonal()
Dim a(1 To 5, 1 To 5) As Integer
Dim sum As Integer, i, j
sum = 0
For i = 1 To 5
For j = 1 To 5
a(i, j) = InputBox("Element : " & i & j)
Cells(i, j) = a(i, j)
Next j
sum = sum + a(i, i)
Next i
MsgBox sum
End Sub

Public Sub m1()
Dim i, j
For i = 1 To 5
For j = i + 1 To 5
Cells(i, j) = "*"
Next j
Next i
End Sub

Public Sub diagonal()
Dim a(1 To 5, 1 To 5) As Integer
Dim sum As Integer, i, j
sum = 0
For i = 1 To 5
For j = 1 To 5
a(i, j) = Cells(i, j)
Next j
sum = sum + a(i, i)
Next i
MsgBox sum
End Sub