3387:练67.1 斐波那契数列
时间: 2024-04-13 15:24:15 浏览: 10
斐波那契数列是一个经典的数学问题,可以用递归或循环的方式来求解。根据提供的引用内容,可以使用循环的方式来求解斐波那契数列的第n项。下面是一个示例代码:
```python
def fib(n):
n1 = 1
n2 = 1
if n == 0:
return 0
if n < 3:
return 1
for i in range(3, n+1):
n3 = (n1 + n2) % 1000000007
n1 = n2
n2 = n3
return n3
print(fib(5)) # 输出:5
```
这段代码中,我们使用三个变量n1、n2和n3来保存斐波那契数列的前三项。然后通过循环计算出第n项的值,并将结果取模1e9+7。最后返回第n项的值。
相关问题
java.lang.NoClassDefFoundError: com/ibm/icu/util/StringTokenizer
这个错误通常是由于缺少 ICU4J 库导致的。ICU4J 是一个开源的国际化组件,提供了许多与语言和文化相关的功能。您需要将 ICU4J 库添加到您的项目中,以解决这个问题。
如果您使用的是 Maven,则可以将以下依赖项添加到您的 pom.xml 文件中:
```
<dependency>
<groupId>com.ibm.icu</groupId>
<artifactId>icu4j</artifactId>
<version>67.1</version>
</dependency>
```
如果您使用的是 Gradle,则可以将以下依赖项添加到您的 build.gradle 文件中:
```
implementation 'com.ibm.icu:icu4j:67.1'
```
This simple class contains four instance variables, noting that they are defined as ‘public’. Add more codes as below to instantiate the class Person and initialize some instance variables. class Program { static void Main(string[ ] args) { Person David = new Person(); Person Alice = new Person(); // Initialize David David.age = 21; David.name = "David"; David.weight = 185.4; David.height = 72.3; // Initialize Alice Alice.age = 18; Alice.name = "Alice"; Alice.weight = 125.7; Alice.height = 67.1; // print some values Console.WriteLine("David’s age = {0}; David’s weight = {1}",David.age, David.weight); Console.WriteLine("Alice’s age = {0}; Alice’s weight = {1}", Alice.age, Alice.weight); } } Properties in C#: In the previous, we accessed the characteristics of the Person Class using some public methods such as ‘setXXX(…)’ and ‘getXXX()’. C# gives us a more controlled way to access these data, called properties. Search the internet (‘Baidu’ or ‘Google’) about the property and amend the code above accordingly using the property. (Task 1.3)
class Person
{
public int Age { get; set; }
public string Name { get; set; }
public double Weight { get; set; }
public double Height { get; set; }
}
class Program
{
static void Main(string[] args)
{
Person David = new Person();
Person Alice = new Person();
// Initialize David
David.Age = 21;
David.Name = "David";
David.Weight = 185.4;
David.Height = 72.3;
// Initialize Alice
Alice.Age = 18;
Alice.Name = "Alice";
Alice.Weight = 125.7;
Alice.Height = 67.1;
// Print some values
Console.WriteLine("David’s age = {0}; David’s weight = {1}", David.Age, David.Weight);
Console.WriteLine("Alice’s age = {0}; Alice’s weight = {1}", Alice.Age, Alice.Weight);
}
}
In the modified code, we have replaced the public instance variables with properties in the Person class. Properties provide a more controlled way to access and modify data.
Properties are defined using the `{ get; set; }` syntax. They allow you to get the value of the property using `PropertyName` and set the value using `PropertyName = value`.
In the Main method, we now use the properties `Age`, `Name`, `Weight`, and `Height` to initialize the attributes for David and Alice. When printing the values, we access the property values directly.
Using properties instead of public instance variables provides encapsulation and allows for better control over data access.