Simplify this expression represented by the map
$$\begin{matrix} 1 & 1 & 0 & 1\\ 0 & 0 & 0 & 0\\ 1 & 1 & 1 & 1\\ 1 & 1 & 0 & 1 \end{matrix}$$
With variables $a,b,c,d$.
Should I be concerned I am not given the labels at the sides? I mean, can I interpret the map as
$$\begin{matrix} & ab & ab' & a'b' & a'b\\ cd & 1 & 1 & 0 & 1\\ cd' & 0 & 0 & 0 & 0\\ c'd' & 1 & 1 & 1 & 1\\ c'd & 1 & 1 & 0 & 1 \end{matrix}$$
Or
$$\begin{matrix} & ac & ac' & a'c' & a'c\\ bd & 1 & 1 & 0 & 1\\ bd' & 0 & 0 & 0 & 0\\ b'd' & 1 & 1 & 1 & 1\\ b'd & 1 & 1 & 0 & 1 \end{matrix}$$
Or etc etc?