Python
```python
def sum_of_numbers(n):
sum = 0
for i in range(1, n+1):
sum += i
return sum
```
或者使用等差数列公式:
```python
def sum_of_numbers(n):
return n * (n + 1) // 2
```
Java
```java
import java.util.Scanner;
public class SumCalculator {
public static int sum(int n) {
if (n == 1) {
return 1;
}
return sum(n - 1) + n;
}
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
System.out.print("输入n:");
int n = s.nextInt();
int sum = sum(n);
System.out.println("从1加到" + n + "的结果为:" + sum);
}
}
```
JavaScript
```javascript
function sum(n) {
var sum = 0;
for (var i = 1; i <= n; i++) {
sum += i;
}
return sum;
}
```
或者使用等差数列公式:
```javascript
function sum(n) {
return n * (n + 1) / 2;
}
```
C++
```cpp
include
int sum(int n) {
if (n == 1) {
return 1;
}
return sum(n - 1) + n;
}
int main() {
int n;
std::cin >> n;
std::cout << "从1加到"<< n << "的结果为:" << sum(n) << std::endl;
return 0;
}
```
C
```csharp
using System;
class SumCalculator {
public static int Sum(int n) {
if (n == 1) {
return 1;
}
return Sum(n - 1) + n;
}
public static void Main() {
Console.Write("输入n:");
int n = int.Parse(Console.ReadLine());
int sum = Sum(n);
Console.WriteLine("从1加到" + n + "的结果为:" + sum);
}
}
```
这些代码示例展示了如何使用循环、递归和数学公式来计算从1加到n的和。你可以根据具体的编程需求和偏好选择合适的方法。