3. A travel company offers a touring holiday which stops at four locations, \(A , B , C\) and \(D\). The tour may be taken with the locations appearing in any order, but the number of days spent in each location is dependent on its position in the tour, as shown in the table below.
| \multirow{2}{*}{} | Stage |
| 1 | 2 | 3 | 4 |
| A | 7 | 8 | 5 | 6 |
| \(B\) | 6 | 9 | 6 | 5 |
| C | 9 | 8 | 5 | 7 |
| \(D\) | 7 | 7 | 6 | 6 |
Showing the state of the table at each stage, use the Hungarian algorithm to find the order in which to complete the tour so as to maximise the total number of days. State the maximum total number of days that can be spent in the four locations.