#include <basico.h>

algoritmo

   braizq="[", brader="]" // bug de Hopper :(

   largo de datos=0
   preparar datos (DATA_BRACKET)
   obtener tamaño de datos, menos '1', guardar en 'largo de datos'

   iterar

        bra="", obtener dato, guardar en 'bra'

        i=1, b=0, error_pos=""
        iterar grupo( ++i, #( i<=len(bra) && is not neg (b) ),\
               #( b += ((bra[i]==braizq) - (bra[i]==brader)) )\
               #( error_pos = cat(replicate(" ",i-1),"^\n") ) )

        solo si ( #(is pos(b)),\
             #( error_pos=cat(cat(" ",error_pos),"(missing closed bracket)\n\n")))

        solo si ( #(is neg(b)),\
             #( error_pos=cat(error_pos,"(extra closed bracket)\n\n")))

        imprimir ( #( rpad(" ",40,bra) ), ": ", \
                   solo si (b, "un"), "balanced\n",\
                   solo si (b, error_pos) )

   mientras ' largo de datos-- '

terminar

subrutinas

DATA_BRACKET:
   datos ("","[ [ ] [ [[] ][] ] [[]] ]","[[ ][[[ ][ ]]",\
          "[][][[]]][","][[]][] [[[]]] [][]","[][]  [][][[]]",\
          "[ a-b * [c/d] + [[10 * sin 30 ]-1] ]",\
          "[ a-b * [c/d] + [[10 * sin 30 ]]-1] ]")
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