Identify the bug in the following code snippet for Two City Scheduling:

Identify the bug in the following code snippet for Two City Scheduling:

def twoCitySchedCost(costs):
    costs.sort(key=lambda x: abs(x[0] - x[1]))
    n = len(costs) // 2
    total = 0
    for i, cost in enumerate(costs):
        if i < n:
            total += cost[0]
        else:
            total += cost[1]
    return total