The code below recursively creates a stream from an array, using concatenation.

const arr $=[1,2,...,14]$; $//$ all numbers from $1$ to $14$ function concat$($s$1$: Stream, s$2$: Stream$)$: Stream $\{$ return s$1.$isEmpty$()?$ s$2$ : snode$($s$1.$head$(),()=>$ concat$($s$1.$tail$(),$ s$2))$; $\}$ function arr$2$strm$($a: T$[],$ start: number, len: number$)$: Stream $\{$ if $($len $===1)\{$ return snode$($a$[$ start$],$ sempty$)$; $\}$ const half $=($len $-$ len $\%2)/2$; return concat$($arr$2$strm$($a$,$ start, half$),$ arr$2$strm$($a$,$ start $+$ half, len $-$ half$))$; $\}$ const s $=$ arr$2$strm$($arr$,0,$ arr.length$)$;

How many nodes are created with snode$()$ by this code?