Given the string below, find the longest substring that is a valid Dyck expression and return the length of this valid substring. A Dyck expression is a balanced string of brackets. The set of Dyck words forms a Dyck language. For instance, the following expression is a valid Dyck expression: $(($a $+$ b$)*($c $-$ d$)).$ The following expressions are NOT valid Dyck languages: $[($a$].$ In this case, the method should return $1($since only $\text{'}$a$\text{'}$ is valid$).$

Examples:

$1)\text{'}[($a$]\text{'}->$ the function returns $\text{'}$a$\text{'}$ and the answer is $1.$

$2)\text{'}\backslash ([($a$+$b$)]\text{'}\backslash )->$ this is valid, so the answer is $9.$

$3)\text{'}\backslash ([($a$+$b$]\text{'}->\backslash )$ the function returns $\text{'}$a $\backslash (+$b $\backslash )\text{'}$ and the answer is $5.$

$4)\text{'}((\backslash \{$a $+$ b$)*\backslash (($c$-$d$))^\{\backslash$prime$\}->\backslash )$ the function returns $\text{'}*\backslash (($c$-$d$)\backslash )\text{'}$ and the answer is $10.$

$1.)$ Find the longest substring that is a valid Dyck expression and return the length of this valid substring:

$```$

s$1=\text{'}\{\}\{[]$m$\}$HIBf$(\{\})$O$(\{($O$[])$p$\}$r$)$V$[]\{\}$A$[$W$]$hTmgf$()()$F$\{\}$lxRSUWClDNQSNBaYJ$\{$T$\}[)]$HfpGZE$[]($A$\{$H$\}$a

$\{$k$\}\{[[]$z$[$gS$()($q$)]]\}[$k$[[]$cS$]])$FzcF$\{\{\}$dh$\}$gcBbDdw$($K$)$hgVt$\{\}$O$[]$f$\{\}$ruNn$\text{'}$

$```$

Attempt $\backslash$#$2$: $0/3($Score: $\backslash (0/3\backslash ))$

Allowed attempts: $5$ Retry penalty: $\backslash (10\backslash \%\backslash )$

$2.)$ Find the longest substring that is a valid Dyck expression and return the length of this valid substring:

$```$

s$2=$ 'egc$[]$aGMgzROGwVvc$[\{($Y$\{\}\{\})[()\{\}$V$]$wJX$()\}]($Kf$[$F$]())$m$)()$l$)($W$)\{\}$DgrFPRMSSr$[$B$]$X$($y$\{\}\{\}$V$)$zz$\{\}$

pZ$[]$j$[]$T$((\{\}[]$V$))$gqif$()$DOhW$[()]$eptUavfWuM$([])$WggiZvN$\{\}($q$)()$Y$\{\}$Tq$\text{'}$

$```$

Points possible: $3$

Allowed attempts: $5$ Retry penalty: $\backslash (10\backslash \%\backslash )$

Already tried $8$ and $43$ from my previous code, both wrong. It is supposed to be in python. Any help is appreciated.