48 lines
1009 B
Bash
Executable File
48 lines
1009 B
Bash
Executable File
#!/usr/bin/env bash
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# Ensure we are given three parameters
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if [ $# -ne 3 ]; then
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echo "Please run this script like: ./$0 <operand1> <operator> <operand2>"
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echo "where operator is either +, -, * or /. You may need to escape or"
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echo "single quote it."
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exit 1
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fi
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# Store the operands and operator
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operand1=$1
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operator=$2
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operand2=$3
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# The main case/switch which was required in the exercise
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case $operator in
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'+')
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result=$((operand1 + operand2))
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operatorWord="plus"
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;;
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'-')
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result=$((operand1 - operand2))
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operatorWord="minus"
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;;
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'*')
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result=$((operand1 * operand2))
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operatorWord="multiplied by"
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;;
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'/')
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if [ "$operand2" -eq 0 ]; then
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echo "The laws of mathematics don't allow division by zero."
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exit 1
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else
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result=$((operand1 / operand2))
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operatorWord="divided by"
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fi
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;;
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# Let's not forget default case either
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*)
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echo "Please use operator +, -. * or /"
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exit 1
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;;
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esac
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# and finally the output in format wanted by the task
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echo "$operand1 $operatorWord $operand2 equals $result"
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