[tex]\it a,\ b,\ c,\ d=cifre\\ \\ a^a=\overline{bcd}\ \ \ \ (*)\\ \\ \overline{bcd}\ are\ trei\ cifre \stackrel{(*)}{\Longrightarrow}\ a^a\ are\ trei\ cifre \Rightarrow a=4\ (singura\ solu\c{\it t}ie)\\ \\ a=4 \stackrel{(*)}{\Longrightarrow}\ \overline{bcd}=4^4 \Rightarrow \overline{bcd}=256 \Rightarrow b=2,\ c=5,\ d=6\\ \\ \overline{cd}-\overline{ab}=56-42=14[/tex]
