Let $A=\left\{x_1, x_2, x_3, x_4, x_5\right\}, B=\left\{y_1, y_2, y_3, y_4\right\}.$ A function $\text{'}f\text{'}$ is defined from $A$ to $B$, such that $f\left(x_1\right)=y_1$ and $f\left(x_2\right)=y_2$, if the number of onto functions from $A$ to $B$ is $n$, then $(n-10)$ is