So here is the Question :-
A Dyck $n$-path is a lattice path of n upsteps $(x,y)$ $\rightarrow$ $(x + 1,y + 1)$ and $n$ downsteps $(x,y) \rightarrow (x + 1,y-1)$ that starts at the origin and never dips below the $x$-axis. A downramp of length $m$ is an upstep followed by $m$ downsteps ending on the $x$ axis. Find a bijection between the $(n-1)$ paths and the $n$-paths which have no downramps of even length.
I know the definition of Dyck-path , it is a staircase walk from $(0,0)$ to $(n,n)$ that strictly lies below the diagonal joining $(0,0)$ and $(n,n)$ , and got the definition of a downramp . But I am not sure how to show a bijection , can anyone help ?