21 lines
526 B
Awk
21 lines
526 B
Awk
# syntax: GAWK -f SEMORDNILAP.AWK unixdict.txt
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{ arr[$0]++ }
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END {
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PROCINFO["sorted_in"] = "@ind_str_asc"
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for (word in arr) {
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rword = ""
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for (j=length(word); j>0; j--) {
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rword = rword substr(word,j,1)
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}
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if (word == rword) { continue } # palindrome
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if (rword in arr) {
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if (word in shown || rword in shown) { continue }
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shown[word]++
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shown[rword]++
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if (n++ < 5) { printf("%s %s\n",word,rword) }
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}
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}
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printf("%d words\n",n)
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exit(0)
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}
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