Sum of powers

You are given natural numbers $n$ and $k$. Find $1^k + 2^k + \ldots + n^k$.

A single line with two integers $n$ and $k$ ($1 \le n \le 20$, $1 \le k \le 12$).

A single integer — the sum.

Compute each $i^k$ with an inner loop (multiply by $i$ $k$ times) while the outer loop runs $i$ from $1$ to $$. returns a floating-point number and loses precision on large values.