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#!/bin/bashCADENA=abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789ARCHIVO=$1i=1j=1while [ $j != 4  ]do		if [ $j = 1 ]	then        	while [ $i != 63  ]		do			echo `expr substr $CADENA ${i} 1`			i=$[i+1]				done	fi	if [ $j != 1 ]	then    		while [ $i != 63  ]		do			echo `expr substr $CADENA ${j} 1``expr substr $CADENA ${i} 1`			i=$[i+1]				done	fi	j=$[j+1]done