18 lines
378 B
Bash
18 lines
378 B
Bash
str="abc qrdef qrghi"
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n=6
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m=3
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expr "x$str" : "x.\{$n\}\(.\{1,$m\}\)"
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expr "x$str" : "x.\{$n\}\(.*\)"
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expr "x$str" : "x\(.*\)."
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index() {
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i=0 s=$1
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until test "x$s" = x || expr "x$s" : "x$2" >/dev/null; do
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i=`expr $i + 1` s=`expr "x$s" : "x.\(.*\)"`
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done
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echo $i
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}
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expr "x$str" : "x.\{`index "$str" r`\}\(.\{1,$m\}\)"
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expr "x$str" : "x.\{`index "$str" qr`\}\(.\{1,$m\}\)"
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