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42 lines
498 B
Bash
42 lines
498 B
Bash
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#!/usr/bin/env bash
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echo "input param: " $1 $2 $3
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x=0
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if [[ -n $1 ]]; then
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x=$1
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fi
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oper=""
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if [[ -n $2 ]]; then
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oper=$2
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fi
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y=0
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if [[ -n $3 ]]; then
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y=$3
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fi
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exec
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case ${oper} in
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+ | add)
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val=`expr ${x} + ${y}`
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echo "${x} + ${y} = ${val}"
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;;
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- | sub)
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val=`expr ${x} - ${y}`
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echo "${x} - ${y} = ${val}"
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;;
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* | mul)
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val=`expr ${x} \* ${y}`
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echo "${x} * ${y} = ${val}"
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;;
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/ | div)
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val=`expr ${x} / ${y}`
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echo "${x} / ${y} = ${val}"
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;;
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*)
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echo "Unknown oper!"
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;;
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esac
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