从值字典数组中检索键

I would to know how to get key if I have the values. Which class get higher marks?

如果我有值,我会知道如何获得密钥。哪个班级得分更高?

let higherMarks = [
"ClassA": [10,20,30,40,50,60],
"ClassB": [15,25,35,45,55,65],
"ClassC": [18,28,38,48,58,68],
]

var largest = 0

var className = ""

for (classTypes, marks) in higherMarks {
for mark in marks {
    if mark > largest {
        largest = mark
    }   
  }
}
print(largest)

1 个解决方案

#1

What I'm saying in my comment is that you need to get the classTypes when you get the mark. Because when you get the higher mark, you want to also get the corresponding key value.

我在评论中说的是,你得到标记时需要获得classTypes。因为当您获得更高的分数时,您还希望获得相应的键值。

Keeping your code's logic I would do something like this:

保持代码的逻辑我会做这样的事情:

let higherMarks = [
    "ClassA": [10,20,30,40,50,60],
    "ClassB": [15,25,35,45,55,65],
    "ClassC": [18,28,38,48,58,68],
]

func findBestClass(in results: [String: [Int]]) -> (name: String, score: Int) {
    var largest = 0
    var type = ""
    for (classType, marks) in results {
        if let max = marks.max(), max > largest {
            largest = max
            type = classType
        }
    }
    return (type, largest)
}

let best = findBestClass(in: higherMarks)

print("The best class is \(best.name) with a score of \(best.score).")

I just replaced your inner loop with .max() and changed the name of the key variable because it should not be plural. My method also returns a tuple because I find it relevant in this situation. But I didn't change your logic, so you can see what I meant by "also get the classTypes".

我只是用.max()替换你的内部循环并更改了键变量的名称,因为它不应该是复数。我的方法也返回一个元组,因为我发现它在这种情况下是相关的。但是我并没有改变你的逻辑,所以你可以看到我的意思“也得到了classTypes”。

#1