I can't figure out the Flow in and Flow Out

Problem 6-23 (Algorithmic)

Find the shortest route from node 1 to node 7 in the network shown. If the constant is "1" it must be entered in the box. If your answer is zero enter "0". For negative values enter "minus" sign (-).

2 6 12 7 6 18 6 4 3 18 7 61 if the arc from node i to node j is on the shortest route Let y = 10 otherwise V X25 3 V 7 V X23 + 6 X14+ Min 12 V X12 + 6 V X13 + 6 V X52 + 6 V X53 7 V X32 + 6 V X35 + 3 X46 + 4 X65 + V X67 + 4 V X56 + 18 V X57 + V 18 s.t.\fFlow In 1 X12 + X32 + X52 + X13 + X23 + X53 = X14 = 0 X25 + X35 + X65 O + X46 + X56 0 + X57 + X67 1 *ij 2 0 for all i and jOptimal Solution: Variable Value 0 X12 0 X13 1 X14 0 X23 X25 X32 0 X35 1 X46 X52 X53 0 X56 X57 0 X65 1 X67Shortest Route: 1-4-6-7 Length = 24 Feedback Check My Work Partially correct