#!/bin/bash

mkfifo mylist

exec 2<>mylist

a1=0

a2=0

a3=0

a4=0

a5=0

for((i=0;i<=2;i++));

do

{

{

if [ $a2 -eq 0 ] && [ $a5 -eq 0 ]

then

sleep 1

echo "A start eatting"

echo "A has eaten"

a1=1

sleep 1

else

a1=0

sleep 1

fi

}&

{

if [ $a1 -eq 0 ] && [ $a3 -eq 0 ]

then

sleep 1

echo "B start eatting"

echo "B has eaten"

a2=1

sleep 1

else

a2=0

sleep 1

fi

}&

{

if [ $a2 -eq 0 ] && [ $a4 -eq 0 ]

then

sleep 1

echo "C start eatting"

echo "C has eaten"

a3=1

sleep 1

else

a3=0

sleep 1

fi

}&

{

if [ $a3 -eq 0 ] && [ $a5 -eq 0 ]

then

sleep 1

echo "D start eatting"

echo "D has eaten"

a4=1

sleep 1

else

a4=0

sleep 1

fi

}&

{

if [ $a4 -eq 0 ] && [ $a1 -eq 0 ]

then

sleep 1

echo "E start eatting"

echo "E has eaten"

a5=1

sleep 1

else

a5=0

sleep 1

fi

}&

wait

}?

done

echo "ABCDE have all eaten"

exec 2<&-

exec 2>&-

rm -f mylist