如何在Swift中检查字符串是否对称

func isSymmetric(_ str: String) -> Bool {
    let chars = Array(str)
    var start = 0
    var end = chars.count - 1
    
    while start < end {
        if chars[start] != chars[end] {
            return false
        }
        start += 1
        end -= 1
    }
    
    return true
}

let str = "abcba"
if isSymmetric(str) {
    print("字符串是对称的")
} else {
    print("字符串不对称")
}