#!/bin/bash

echo "Enter your YEAR and MONTH"
#"Enter your YEAR and MONTH"と表示する.
echo YEAR
#YEARと表示し,入力を促す.
read YEAR
#YEARに年を読み込む.
echo MONTH
#MONTHと表示し,入力を促す.
read MONTH
#MONTHに月を読み込む.

echo $YEAR"年"$MONTH"月"
cal=("日" "月" "火" "水" "木" "金" "土")
#配列"cal"に曜日を作る.

#各月ごとに,ツェラーの公式を計算する.

X=`expr $YEAR % 4`
Y=`expr $YEAR % 100`
Z=`expr $YEAR % 400`

if [ $MONTH = 1 ]
#1月の場合.

   then y=`expr $((YEAR - 1))`
        m=`expr $((MONTH + 12))`
        y1=`expr $((y / 4))`
        y2=`expr $((y / 100))`
        y3=`expr $((y / 400))`
        m1=`expr $((((m * 13) + 8) / 5))`
        s=`expr $(((y + y1 - y2 + y3 + m1 + 1) % 7))`
        sp=`expr $s`

        t=1

        while :
         do
          if [ $t -gt $sp ]
           then break
          fi
          u=`expr $t + 6`
          cal[$u]=" "
          t=`expr $t + 1`
         done

        t=1
        v=31

        while :
         do
          if [ $t -gt $v ]
           then break
          fi
          u=`expr $t + 6 + $sp`
          cal[$u]=$t
          t=`expr $t + 1`
         done

        printf "%2s %2s %2s %2s %2s %2s %2s\n" "${cal[@]}"


elif [ $MONTH = 2 ]
#2月の場合(閏年の場合とそれ以外の場合を分けて考える.)

 then

  if [ $X = 0 ] || [ $Y = 0 ] || [ $Z != 0 ]
  #閏年の場合.

   then y=`expr $((YEAR - 1))`
        m=`expr $((MONTH + 12))`
        y1=`expr $((y / 4))`
        y2=`expr $((y / 100))`
        y3=`expr $((y / 400))`
        m1=`expr $((((m * 13) + 8) / 5))`
        s=`expr $(((y + y1 - y2 + y3 + m1 + 1) % 7))`
        sp=`expr $s`

        t=1

        while :
         do
          if [ $t -gt $sp ]
           then break
          fi
          u=`expr $t + 6`
          cal[$u]=" "
          t=`expr $t + 1`
         done

        t=1
        v=29

        while :
         do
          if [ $t -gt $v ]
           then break
          fi
          u=`expr $t + 6 + $sp`
          cal[$u]=$t
          t=`expr $t + 1`
         done

        printf "%2s %2s %2s %2s %2s %2s %2s\n" "${cal[@]}"


   else
   #閏年でない場合.

        y=`expr $((YEAR - 1))`
        m=`expr $((MONTH + 12))`
        y1=`expr $((y / 4))`
        y2=`expr $((y / 100))`
        y3=`expr $((y / 400))`
        m1=`expr $((((m * 13) + 8) / 5))`
        s=`expr $(((y + y1 - y2 + y3 + m1 + 1) % 7))`
        sp=`expr $s`

        t=1

        while :
         do
          if [ $t -gt $sp ]
           then break
          fi
          u=`expr $t + 6`
          cal[$u]=" "
          t=`expr $t + 1`
         done

        t=1
        v=28

        while :
         do
          if [ $t -gt $v ]
           then break
          fi
          u=`expr $t + 6 + $sp`
          cal[$u]=$t
          t=`expr $t + 1`
         done

        printf "%2s %2s %2s %2s %2s %2s %2s\n" "${cal[@]}"


  fi


elif [ $MONTH = 4 ] || [ $MONTH = 6 ] || [ $MONTH = 9 ] || [ $MONTH = 11 ]
#4,6,9,11月の場合.

   then y=`expr $YEAR`
        m=`expr $MONTH`
        y1=`expr $((y / 4))`
        y2=`expr $((y / 100))`
        y3=`expr $((y / 400))`
        m1=`expr $((((m * 13) + 8) / 5))`
        s=`expr $(((y + y1 - y2 + y3 + m1 + 1) % 7))`
        sp=`expr $s`

        t=1

        while :
         do
          if [ $t -gt $sp ]
           then break
          fi
          u=`expr $t + 6`
          cal[$u]=" "
          t=`expr $t + 1`
         done

        t=1
        v=30

        while :
         do
          if [ $t -gt $v ]
           then break
          fi
          u=`expr $t + 6 + $sp`
          cal[$u]=$t
          t=`expr $t + 1`
         done

        printf "%2s %2s %2s %2s %2s %2s %2s\n" "${cal[@]}"


   else
   #3,5,7,8,10,12月の場合.

        y=`expr $YEAR`
        m=`expr $MONTH`
        y1=`expr $((y / 4))`
        y2=`expr $((y / 100))`
        y3=`expr $((y / 400))`
        m1=`expr $((((m * 13) + 8) / 5))`
        s=`expr $(((y + y1 - y2 + y3 + m1 + 1) % 7))`
        sp=`expr $s`

        t=1

        while :
         do
          if [ $t -gt $sp ]
           then break
          fi
          u=`expr $t + 6`
          cal[$u]=" "
          t=`expr $t + 1`
         done

        t=1
        v=31

        while :
         do
          if [ $t -gt $v ]
           then break
          fi
          u=`expr $t + 6 + $sp`
          cal[$u]=$t
          t=`expr $t + 1`
         done

        printf "%2s %2s %2s %2s %2s %2s %2s\n" "${cal[@]}"


fi

echo $YEAR"年"$MONTH"月" > quiz2.txt
     printf "%2s %2s %2s %2s %2s %2s %2s\n" "${cal[@]}" >> quiz2.txt
#結果を"quiz2.txt"に出力する.