如何在for循环中排序(迅速)

Question

let vehicles = ["unicycle" : 1, "bicycle":2, "tricycle":3, "quad bike": 4]
for (vehicleName, wheelCount) in vehicles {

    print (" \(vehicleName) has \(wheelCount) wheels")
      
}`

打印结果是：

四轮自行车有四个轮子独轮车有一个轮子三轮车有三个轮子自行车有两个轮子

我如何根据它们的车轮数量对它们进行排序，这样打印出来的结果就像：

独轮车有一个轮子自行车有两个轮子三轮车有三个轮子四轮自行车有四个轮子

Answer 1

你可以用

let vehicles = ["unicycle" : 1, "bicycle": 2, "tricycle": 3, "quad bike": 4]
let sortedVehicles = vehicles.sorted { $0.value < $1.value }
for (vehicleName, wheelCount) in sortedVehicles {
    print ("\(vehicleName) has \(wheelCount) wheels")
}

输出：

unicycle has 1 wheels
bicycle has 2 wheels
tricycle has 3 wheels
quad bike has 4 wheels

Answer 2

let vehicles = ["unicycle" : 1, "bicycle":2, "quad bike": 4, "tricycle":3]
let sortedVehicles = vehicles.sorted { $0.1 < $1.1 }
print(sortedVehicles) //Prints [(key: "unicycle", value: 1), (key: "bicycle", value: 2), (key: "tricycle", value: 3), (key: "quad bike", value: 4)]
sortedVehicles.forEach {
    print("\($0.key) has \($0.value) wheels")
}

结果：

unicycle has 1 wheels
bicycle has 2 wheels
tricycle has 3 wheels
quad bike has 4 wheels

Answer 3

let vehicles = ["unicycle" : 1, "bicycle" : 2, "tricycle" : 3, "quadbike" : 4].sorted {
    return $0.value > $1.value
}
for (vehicieName, wheelCount) in vehicles {
    print("\(vehicieName) has \(wheelCount) wheels")
}

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