Python
```python
def sum_of_numbers(n):
return (n * (n + 1)) // 2
n = int(input("请输入一个正整数n:"))
result = sum_of_numbers(n)
print("从1加到n的和为:", result)
```
Java
```java
import java.util.Scanner;
public class Main {
public static int sumOfNumbers(int n) {
return (n * (n + 1)) / 2;
}
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print("请输入一个正整数n:");
int n = scanner.nextInt();
int result = sumOfNumbers(n);
System.out.println("从1加到n的和为: " + result);
}
}
```
C++
```cpp
include
int sumOfNumbers(int n) {
return (n * (n + 1)) / 2;
}
int main() {
int n;
std::cout << "请输入一个正整数n:";
std::cin >> n;
int result = sumOfNumbers(n);
std::cout << "从1加到n的和为: " << result << std::endl;
return 0;
}
```
JavaScript
```javascript
function sumOfNumbers(n) {
return (n * (n + 1)) / 2;
}
const readline = require('readline');
const rl = readline.createInterface({
input: process.stdin,
output: process.stdout
});
rl.question('请输入一个正整数n:', function(n) {
const result = sumOfNumbers(parseInt(n));
console.log(`从1加到n的和为: ${result}`);
rl.close();
});
```
C
```csharp
using System;
class Program {
static int SumOfNumbers(int n) {
return (n * (n + 1)) / 2;
}
static void Main() {
Console.Write("请输入一个正整数n:");
int n = int.Parse(Console.ReadLine());
int result = SumOfNumbers(n);
Console.WriteLine("从1加到n的和为: " + result);
}
}
```
Ruby
```ruby
def sum_of_numbers(n)
(n * (n + 1)) / 2.0
end
puts "请输入一个正整数n:"
n = gets.chomp.to_i
result = sum_of_numbers(n)
puts "从1加到n的和为: {result}"
```
这些代码示例分别使用Python、Java、C++、JavaScript、C和Ruby编程语言实现了从1加到n的功能。每种语言的代码都采用了等差数列求和公式`S = n * (n + 1) / 2`来计算结果,并通过用户输入获取n的值,最后输出计算结果。