Задача на максимальный поток в Visual Basic

Private Sub Form_Load()
Dim a()
Dim b()
Dim n As Integer
Dim Min As Integer
n = 25
ReDim a(n, n)
ReDim b(n, n)
Dim l(1 To 25) As Integer
Dim m(1 To 25) As Integer
Dim i%, j%
Dim s As String, st As String
Dim phi As String
 
For i = 1 To n ' îáíóëåíèå âñåõ çíà÷åíèé ìàññèâà ñ ðàññòîÿíèÿìè
For j = 1 To n
   a(i, j) = 0
Next j
Next i
 
a(1, 2) = 248: a(1, 5) = 337: a(1, 6) = 273
a(2, 3) = 151: a(2, 4) = 210: a(2, 5) = 133: a(2, 6) = 141
a(3, 4) = 70: a(3, 5) = 166
a(4, 5) = 156: a(4, 8) = 194: a(4, 10) = 192
a(5, 6) = 150: a(5, 7) = 172: a(5, 8) = 107
a(6, 7) = 139
a(7, 8) = 184
a(8, 9) = 118: a(8, 10) = 183
a(9, 10) = 127: a(9, 12) = 424: a(9, 14) = 341: a(9, 15) = 310: a(9, 16) = 428
a(10, 12) = 131
a(11, 12) = 492: a(11, 13) = 143: a(11, 14) = 186: a(11, 15) = 302: a(11, 18) = 337: a(11, 19) = 344: a(11, 20) = 449
a(12, 16) = 137
a(13, 14) = 297: a(13, 18) = 335: a(13, 19) = 405: a(13, 20) = 558
a(14, 15) = 137: a(14, 18) = 361: a(14, 20) = 289
a(15, 16) = 181: a(15, 19) = 245: a(15, 20) = 243: a(15, 21) = 301
a(16, 17) = 63: a(16, 20) = 319
a(17, 20) = 325: a(17, 21) = 282: a(17, 22) = 268
a(18, 19) = 170: a(18, 23) = 187
a(19, 20) = 186: a(19, 23) = 149: a(19, 24) = 391
a(20, 21) = 79: a(20, 23) = 226: a(20, 24) = 245
a(21, 22) = 388: a(21, 24) = 229
a(22, 24) = 560
a(23, 24) = 301: a(23, 25) = 341
a(24, 25) = 151
 
 
For i = 1 To n 'çàïîëíåíèå ñèììåòðè÷íîé ÷àñòè ìàññèâà ñ ðàñññòîÿíèÿìè
For j = 1 To n
   If a(i, j) <> 0 Then a(j, i) = a(i, j)
Next j
Next i
 
s = "  "
 
For i = 1 To n ' âûâîä íà÷àëüíîãî ìàññèâà ñ ðàññòîÿíèÿìè
For j = 1 To n
   s = s & a(i, j) & "   "
Next j
   s = s & vbCrLf
Next i
 
Label1.Caption = s
 
'îáíóëåíèå âñåõ ôè
For i = 1 To n
For j = 1 To n
   b(i, j) = 0
Next j
Next i
 
 
 
' âûâîä ôè
For i = 1 To n
For j = 1 To n
   phi = phi & b(i, j) & "   "
Next j
   phi = phi & vbCrLf
   
Next i
 Label2.Caption = phi
 
 
 
 
 
End Sub

a(1, 5) = 337