Determining constants in a cubic spline

If the function $s:[0,4]\to\mathbb R$ defined by

$$s(x)=\begin{cases}a(x-2)^2+b(x-1)^2,&0\le x\le1,\\(x-2)^2,&1<x\le3,\\2c(x-2)^2+(x-3)^3,&3<x\le4\end{cases}$$

is a cubic spline, then the value of $2a+b+2c$ is