# C Program to find sum of all natural numbers

Write a C Program to find the sum of all natural numbers from 1 to n using for loop and while loop. How to find the sum of all natural numbers from 1 to n using while and for loop. Logic to find the sum of all natural numbers within the given range using for loop and while loop.

## C Program to find the sum of all natural numbers from 1 to n using for loop

```
#include <stdio.h>
void main()
{
int sum = 0, i, n;
printf("Enter value of n: ");
scanf("%d", &n);
for (i = 1; i <= n; i++)
sum = sum + i;
printf("Sum of numbers 1-%d: %d", n, sum);
}
```

## C Program to find the sum of all natural numbers from 1 to n using while loop

```
#include <stdio.h>
void main()
{
int sum = 0, i = 1, n;
printf("Enter value of n: ");
scanf("%d", &n);
while(i <= n)
{
sum = sum + i;
i++;
}
printf("Sum of numbers 1-%d: %d", n, sum);
}
```

**Output**

```
Enter value of n: 20
Sum of numbers 1-20: 210
```