. 1 ! # / Bin / the bash 2 the while : . 3 do . 4 Read -p " Please enter the calculation rule: " the JS . 5 IF [the JS the -Z $]; the then . 6 Exit . 7 the else . 8 # echo " $` the JS = $ echo the JS | bc` " . 9 echo $ =` the JS awk the BEGIN " {} the JS Print $ " ` 10 Fi . 11 DONE