原文： https://beginnersbook.com/2017/10/c-program-to-find-the-sum-of-first-n-natural-numbers/
程序查找前n个自然数的总和。我们将看到计算自然数的总和的两个 C 程序。在第一个 C 程序中，我们使用for循环查找总和，在第二个程序中，我们使用while循环执行相同操作。
要了解这些程序，您应该熟悉以下 C 编程概念：
用户输入n的值，程序使用for循环计算前n个自然数的总和。
#include <stdio.h>
int main()
{
int n, count, sum = 0;
printf("Enter the value of n(positive integer): ");
scanf("%d",&n);
for(count=1; count <= n; count++)
{
sum = sum + count;
}
printf("Sum of first %d natural numbers is: %d",n, sum);
return 0;
}输出：
Enter the value of n(positive integer): 6
Sum of first 6 natural numbers is: 21#include <stdio.h>
int main()
{
int n, count, sum = 0;
printf("Enter the value of n(positive integer): ");
scanf("%d",&n);
/* When you use while loop, you have to initialize the
* loop counter variable before the loop and increment
* or decrement it inside the body of loop like we did
* for the variable "count"
*/
count=1;
while(count <= n){
sum = sum + count;
count++;
}
printf("Sum of first %d natural numbers is: %d",n, sum);
return 0;
}输出：
Enter the value of n(positive integer): 7
Sum of first 7 natural numbers is: 28看看这些相关的 C 程序：