A sales manager for a large construction equipment company has offices in four Saudi Arabia cities. As part of the monthly assignment, the manager wants a salesman from each office to fly and meet buyers in four other cities. The table below shows the cost of airplane tickets in Saudi Riyal (SAR) between these cities. Find the optimal assignment in order to minimize the monthly airfare cost. L 0 1 

FROM TO CITY A B C D City 1 200 240 350 300 City 2 250 200 380 250 City 3 400 350 400 200 City 4 200 260 340 200