A company is planning to interview 2n people. Given the array costs where costs[i] = [aCosti, bCosti], the cost of flying the ith person to city a is aCosti, and the cost of flying the ith person to city b is bCosti.
Return the minimum cost to fly every person to a city such that exactly n people arrive in each city.
Example 1:
Input: costs = [[10,20],[30,200],[400,50],[30,20]]
Output: 110
Explanation:
The first person goes to city A for a cost of 10.
The second person goes to city A for a cost of 30.
The third person goes to city B for a cost of 50.
The fourth person goes to city B for a cost of 20.
The total minimum cost is 10 + 30 + 50 + 20 = 110 to have half the people interviewing in each city.
Example 2:
Input: costs = [[259,770],[448,54],[926,667],[184,139],[840,118],[577,469]]
Output: 1859
Example 3:
Input: costs = [[515,563],[451,713],[537,709],[343,819],[855,779],[457,60],[650,359],[631,42]]
Output: 3086
答案
func twoCitySchedCost(costs [][]int) int {
res := 0
//先把所有人送往A
for _, c := range costs {
res += c[0]
}
n := len(costs)
refund := make([]int, n)
//计算如果从A退票改签B，可以获取多少净利润
for i := range costs {
refund[i] = costs[i][1] - costs[i][0]
}
//排序
sort.Ints(refund)
for i := 0; i < n/2; i++ {
res += refund[i]
}
return res
}
