Accumulating sum in one line in C#

Question

Is it possible to do this in one line with the goal of getting the accumulated sum equal to n?

int n = 0;
for (int i = 1; i <= 10; i++)
{
    n += i;
}

Answer 1

There's a LINQ extension method for that:

static int SlowSum1ToN(int N)
{
    return Enumerable.Range(1, N).Sum();
}

However, you can also calculate this particular value (the sum of an arithmetic sequence) without iterating at all:

static int FastSum1ToN(int N)
{
    return (N * (1 + N)) / 2;
}

Answer 2

Yes it's possible, you can do that using Enumerable.Range to generate a sequence of integer numbers and then call the LINQ extension method Sum as the following:

int result = Enumerable.Range(1, 10).Sum();