3. Given that $E$ and $F$ are points on the sides $BC$ and $CD$ of square $ABCD$, respectively, and $AE$ and $AF$ intersect the diagonal $BD$ at $M$ and $N$. If $\angle EAF=$ $50^{\circ}$, then $\angle CME+\angle CNF=$ $\qquad$
3. $100^{\circ}$