2019-10-29 18:22:19 +08:00
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#!/usr/bin/env bash
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2019-05-10 11:17:57 +08:00
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# passing parameters to a function
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function addem {
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2019-10-29 18:22:19 +08:00
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if [ $# -eq 0 ] || [ $# -gt 2 ]
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then
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echo -1
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elif [ $# -eq 1 ]
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then
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echo $[ $1 + $1 ]
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else
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echo $[ $1 + $2 ]
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fi
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2019-05-10 11:17:57 +08:00
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}
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echo -n "Adding 10 and 15:"
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value=`addem 10 15`
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echo $value
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echo -n "Let's try adding just one number: "
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value=`addem 10`
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echo $value
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echo -n "Now trying adding no number: "
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value=`addem`
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echo $value
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echo -n "Finally, try adding three or more numbers: "
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value=`addem 10 15 20`
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echo $value
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