From 731896b74400828b498c666954eb4698f4ad4e26 Mon Sep 17 00:00:00 2001
From: satopoppo <satona.oinuma@is-tech.co.jp>
Date: Thu, 29 Apr 2021 15:27:54 +0900
Subject: [PATCH 1/2] =?UTF-8?q?=E3=83=A9=E3=83=B3=E3=82=AD=E3=83=B3?=
 =?UTF-8?q?=E3=82=B0=E3=81=AE=E5=AE=9F=E8=A3=85=E5=AE=8C=E4=BA=86?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 app.js | 43 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

diff --git a/app.js b/app.js
index ad9a93a7..fc900aa1 100644
--- a/app.js
+++ b/app.js
@@ -1 +1,44 @@
 'use strict';
+const fs = require('fs');
+const readline = require('readline');
+const rs = fs.createReadStream('./popu-pref.csv');
+const rl = readline.createInterface({ input: rs, output: {} });
+const prefectureDataMap = new Map(); // key: 都道府県 value: 集計データのオブジェクト 
+rl.on('line',lineString => {
+    //ファイルからデータを抜き出す
+    const columns = lineString.split(',');
+    const year = parseInt(columns[0]);
+    const prefecture = columns[1];
+    const popu = parseInt(columns[3]);
+    if (year === 2010 || year === 2015){
+        let value = prefectureDataMap.get(prefecture);
+        if(!value){
+            value = {   //初期値
+                popu10: 0,
+                popu15: 0,
+                change: null
+            };
+        };
+        if (year === 2010) {    //連想配列に保存。次から同じ県のデータが来れば16行目で保存したオブジェクトが取得される
+            value.popu10 = popu;
+        }
+        if (year === 2015){
+            value.popu15 = popu;
+        }
+        prefectureDataMap.set(prefecture, value);
+    }
+});
+rl.on('close', () => {  
+    for (let [key, value] of prefectureDataMap) {
+    }
+    const rankingArray = Array.from(prefectureDataMap).sort((pair1,pair2) => {
+        return pair2[1].change - pair1[1].change;
+    });
+    // map関数を用いて、Mapの配列を要素[key, value]として受け取り、文字列に変換する処理
+    const rankingStrings = rankingArray.map(([key, value]) => {
+        return (
+            key + ': ' + value.popu10 + '=>' + value.popu15 + ' 変化率:' + value.change
+        );
+    });
+    console.log(rankingStrings);
+});

From 60db9274b97b3c62b6195adea1f9a2efaaadd061 Mon Sep 17 00:00:00 2001
From: satopoppo <satona.oinuma@is-tech.co.jp>
Date: Thu, 29 Apr 2021 15:52:01 +0900
Subject: [PATCH 2/2] =?UTF-8?q?=E4=BA=BA=E3=81=8C=E6=B8=9B=E3=81=A3?=
 =?UTF-8?q?=E3=81=9F=E5=89=B2=E5=90=88=E3=83=A9=E3=83=B3=E3=82=AD=E3=83=B3?=
 =?UTF-8?q?=E3=82=B0=E3=81=AB=E5=A4=89=E6=9B=B4?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 app.js | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/app.js b/app.js
index fc900aa1..25dc77c8 100644
--- a/app.js
+++ b/app.js
@@ -30,14 +30,15 @@ rl.on('line',lineString => {
 });
 rl.on('close', () => {  
     for (let [key, value] of prefectureDataMap) {
+        value.change = value.popu15 / value.popu10;
     }
     const rankingArray = Array.from(prefectureDataMap).sort((pair1,pair2) => {
-        return pair2[1].change - pair1[1].change;
+        return pair1[1].change - pair2[1].change;
     });
     // map関数を用いて、Mapの配列を要素[key, value]として受け取り、文字列に変換する処理
-    const rankingStrings = rankingArray.map(([key, value]) => {
+    const rankingStrings = rankingArray.map(([key, value], i) => {
         return (
-            key + ': ' + value.popu10 + '=>' + value.popu15 + ' 変化率:' + value.change
+            i + 1 + '位 ' + key + ': ' + value.popu10 + '=>' + value.popu15 + ' 変化率:' + value.change
         );
     });
     console.log(rankingStrings);