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encrypt(${\it tab}$;${\it keyv}$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$\=let $K$,$p$,$f$ = ${\it tab}$ in \+
\\[0ex]$<$$K$, $p$+1, if $p$ $<$z $K$ then update($\lambda$$i$,$j$. ($i$ =$_{0}$ $j$);$f$;$p$;$<$($f$($p$)).1, ${\it keyv}$$>$) else $f$ fi $>$
\-
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