A company is planning to interview 2n people. Given the array costs where costs[i] = [aCost_i, bCost_i], the cost of flying the i-th person to city A is aCost_i and the cost of flying the i-th person to city B is bCost_i.
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: Person 0 goes to city A (cost 10), person 1 goes to city A (cost 30), person 2 goes to city B (cost 50), person 3 goes to city B (cost 20). Total = 10 + 30 + 50 + 20 = 110.
Example 2:
Input: costs = [[259,770],[448,54],[926,667],[184,139],[840,118],[577,469]]
Output: 1859
Explanation: The optimal assignment sends persons 0, 3, 5 to city A and persons 1, 2, 4 to city B.
Example 3:
Input: costs = [[515,563],[451,713],[537,709],[343,819],[855,779],[457,60],[650,359],[631,42]]
Output: 3086
Explanation: Send persons 0, 2, 3, 6 to city A and persons 1, 4, 5, 7 to city B for minimum total cost.
2 * n == costs.length2 <= costs.length <= 100costs.length is even1 <= aCost_i, bCost_i <= 1000