問題 51 に別解を追加しました

jq だけでやってみました。

Author: kariya-mitsuru

answer/51.md

@@ -10,3 +10,11 @@ $ cat scores.txt | awk '{$1=sprintf("%03d",$1);print}' | sort | join -a 1 studen
 別解4（山田）$ q "select st.c1, st.c2, CASE WHEN sc.c2 is NULL THEN 0 ELSE sc.c2 END FROM students.txt st LEFT JOIN scores.txt sc ON (st.c1 == sc.c1)" | awk '{$1=sprintf("%03d", $1);print}'
 別解5（中村）$ cat <(awk '{printf "{\"k\":\"%03d\",\"a\":\"%s\"}\n", $1, $2}' students.txt) <(awk '{printf "{\"k\":\"%03d\",\"b\":%s}\n", $1, $2}' scores.txt) | jq -s 'group_by(.k)|map([.[0].k,.[0].a,.[1].b + 0])|.[]|@sh' -r | tr -d "'"
 ```
+
+ ### 読者別解
+
+ by [kariya-mitsuru](https://github.com/kariya-mitsuru)
+
+```
+別解6 $ jq -R '. / " "' students.txt scores.txt | jq -sr 'group_by(.[0] | tonumber) | .[] | add | "\(.[0]) \(.[1]) \(.[3] // 0)"'
+```