如何检查IEnumerable< T>排序?

如何检查IEnumerable< T>排序?

问题描述:

如何检查IEnumerable是否排序?

How to check if a IEnumerable is sorted?

bool IsSorted<T>(IEnumerable<T> enumerable)
{
   ???
}


be:

static bool IsSorted<T>(IEnumerable<T> enumerable) where T : IComparable<T> {
    T prev = default(T);
    bool prevSet = false;
    foreach (var item in enumerable) {
        if (prevSet && (prev == null || prev.CompareTo(item) > 0))
            return false;
        prev = item;
        prevSet = true;
    }
    return true;
}

适用于大多数内置类型,如数字或字符串,因为它们实现了IComparable 。

Works with most built-in types like numbers or strings, because they implement IComparable.