致命错误：索引超出范围（数组）

Question

我对 Swift 和编程很陌生，所以我不知道问题出在哪里。试图在现有主题中找到答案 - 找不到。提前致谢。

func smartAssigning(names: [String], statuses: [Bool], projects: [Int], tasks: [Int]) -> String {
    //beginig
    var collect: [Int] = [], nameLast = 0
    var candidateNumber: [Int] = []
    for x in 0...statuses.count {

        //Defines who is working
        if statuses[x] == false {
            collect.append(x)
        } else {}
    }

    // Checks for min tasks assigned among those not on vacation
    let rt: Int = tasks.min()!
    let rp: Int = projects.min()!
    for i in collect {
        if tasks[i] == rt {
            candidateNumber.append(i)
        } else {}
    }
    // if there is only 1 with min tasks - returns his number in array
    if candidateNumber.count == 1 {
        nameLast = candidateNumber[0]
    } else {
        // checks for min projects
        for e in candidateNumber {
            if projects[e] == rp {
                nameLast = e
            }
        }
    }
    return names[nameLast]
}
smartAssigning(names: ["sd", "dfsd","dfsdf"], statuses: [true, false, false], projects: [2, 1, 1], tasks: [3, 2, 1])

屏幕：

Answer 1

错误在这里：

for x in 0...statuses.count { // Error is here

    //Defines who is working
    if statuses[x] == false {
        collect.append(x)
    } else {}
}

如果statuses.count 是n，那么最大索引是n-1。应该是0..<statuses.count。您应该避免手动创建这样的范围，因为它可能会导致这种错字。最好只做for x in status.indices。

顺便说一句，如果else 不做任何事情，则不需要它。

另外，不要与 false (== false) 进行比较，只需否定 Bool。

for x in statuses.indices { // Error is here
    //Defines who is working
    if !statuses[x] {
        collect.append(x)
    }
}

整个代码可以使用单个filter(_:) 表达式编写：

// TODO: Give me a new meaningful name!
let collect = statues.enumerated() // Get index, status pairs
                     .filter{ index, status in !status } // filter all false statuses
                     .map{ index, status in index } // Take just the indices