Option Explicit


Sub test()
Dim ar( 0  To  3 ,  0  To  3 ) As Long
Dim i As Long, m As Long, k As Long
Dim a, b, c, d
a = Array( 5 ,  2 ,  3 , - 4 )
b = Array(- 6 ,  3 , - 3 ,  5 )
c = Array( 5 , - 6 ,  7 , - 2 )
d = Array(- 4 , - 3 , - 5 , - 2 )

For m =  0  To  3 
ar( 0 , m) = a(i)
i = i +  1 
Next
i =  0 
For m =  0  To  3 
ar( 1 , m) = b(i)
i = i +  1 
Next
i =  0 
For m =  0  To  3 
ar( 2 , m) = c(i)
i = i +  1 
Next
i =  0 
For m =  0  To  3 
ar( 3 , m) = d(i)
i = i +  1 
Next

'1) Из матрицы сформировать одномерный массив, каждый элемент вычислить как произведение 'положительных эл-ов соотв-их с/б матрицы


Dim res As Variant
res = MultColumns(ar)
'
'2) Из матрицы сформировать одномерный массив, каждый элемент которого вычислить как 'произведение элементов соответствующей строки матрицы, лежащих на главной диагонали и 'правее неё


Dim cols As Variant
cols = MultAfterDiagonal(ar)
'3) После первого положительного элемента каждого столбца матрицы вставить максимальный 'элемент столбца
Dim aps As Variant
aps = AppendMaxInRow(ar)

End Sub

Private Function MultColumns(v As Variant) As Variant
ReDim ret(LBound(v,  2 ) To UBound(v,  2 )) As Variant
Dim i As Long
Dim j As Long
Dim cnt As Long
For j = LBound(v,  2 ) To UBound(v,  2 )
Dim tmp
tmp =  1 
For i = LBound(v,  1 ) To UBound(v,  1 )
If v(i, j) >  0  Then
tmp = tmp * v(i, j)
End If
Next
ret(cnt) = tmp
cnt = cnt +  1 
Next
MultColumns = ret

End Function

Function Maximum(ar As Variant) As Variant

    Dim i As Integer, maxi As Variant
    maxi = Null
    For i =  0  To UBound(ar)
        If IsNull(maxi) Then
            maxi = ar(i)
        ElseIf Not IsNull(ar(i)) Then
            If maxi < ar(i) Then
                maxi = ar(i)
            End If
        End If
    Next i
    Maximum = maxi
    
End Function

Private Function MaxColumns(v As Variant) As Variant
If IsNull(UBound(v,  2 )) Then Exit Function
Dim n As Integer, i As Integer, j As Integer
ReDim tmp(LBound(v,  1 ) To UBound(v,  1 )) As Variant
ReDim out(LBound(v,  2 ) To UBound(v,  2 )) As Variant
For j = LBound(v,  2 ) To UBound(v,  2 )

For i = LBound(v,  1 ) To UBound(v,  1 )
tmp(i) = v(i, j)
Debug.Print tmp(i)
Next
out(n) = Maximum(tmp)

n = n +  1 

Next
MaxColumns = out

End Function

Private Function MultAfterDiagonal(v As Variant) As Variant

 ReDim out(LBound(v,  1 ) To UBound(v,  1 )) As Variant
 Dim i As Long, j As Long, n As Long
 For i = LBound(v,  1 ) To UBound(v,  1 )
 Dim tmp
 tmp = v(i, n)
 For j = i +  1  To UBound(v,  2 )
tmp = tmp * v(i, j)
 Next
 out(n) = tmp
n = n +  1 
Next

MultAfterDiagonal = out
End Function

Private Function AppendMaxInRow(v As Variant) As Variant

Dim mx As Variant
mx = MaxColumns(v)
ReDim out(LBound(v,  1 ) To UBound(v,  1 ), LBound(v,  2 ) To UBound(v,  1 ) +  1 )

Dim i As Long, j As Long, k As Variant
For i = LBound(v,  1 ) To UBound(v,  1 )
k = Null
For j = LBound(v,  2 ) To UBound(v,  2 )
If v(i, j) >  0  Then
k = i
Exit For
End If
Next
If IsNull(k) Then
For j = LBound(v,  2 ) To UBound(v,  2 )
out(i, j) = v(i, j)
Next
Else
For j = LBound(v,  2 ) To k
out(i, j) = v(i, j)
Next
out(i, k +  1 ) = mx(i)
For j = k +  2  To UBound(v,  2 ) +  1 
out(i, j) = v(i, j -  1 )
Next
End If
Next

AppendMaxInRow = out

End Function