Midpoint and Linear Interpolation

• std::midpoint(a, b): calculates the midpoint $(a + (b - a) / 2)$ of integers, floating points, or pointers. If a and b are pointers, they have to point to the same array object. The function needs the header <numeric>.
• std::lerp(a, b, t): calculates the linear interpolation $(a + t(b - a))$. When t is outside the range $[0, 1]$, it calculates the linear extrapolation. The function needs the header <cmath>.

The following program applies both functions.