From e960366ec6977a9629accf9678f53665d5c5944f Mon Sep 17 00:00:00 2001
From: Ninomiya Sota <sotalax08@gmail.com>
Date: Mon, 13 Feb 2023 20:27:15 +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 | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/app.js b/app.js
index ad9a93a..c3823f9 100644
--- a/app.js
+++ b/app.js
@@ -1 +1,43 @@
 'use strict';
+const fs = require('fs');
+const readline = require('readline');
+const rs = fs.createReadStream('./popu-pref.csv');
+const rl = readline.createInterface({ input: rs });
+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 => {
+  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 = null;
+    if (prefectureDataMap.has(prefecture)) {
+      value = prefectureDataMap.get(prefecture);
+    } else {
+      value = {
+        popu10: 0,
+        popu15: 0,
+        change: null
+      };
+    }
+    if (year === 2010) {
+      value.popu10 = popu;
+    }
+    if (year === 2015) {
+      value.popu15 = popu;
+    }
+    prefectureDataMap.set(prefecture, value);
+  }
+});
+rl.on('close', () => {
+  for (const [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;
+  });
+  const rankingStrings = rankingArray.map(([key, value]) => {
+    return `${key}: ${value.popu10}=>${value.popu15} 変化率 ${value.change}`;
+  });
+  console.log(rankingStrings);
+});
\ No newline at end of file

From b0ef2802285a3261ada83bb41245bdcdb976143d Mon Sep 17 00:00:00 2001
From: Ninomiya Sota <sotalax08@gmail.com>
Date: Mon, 13 Feb 2023 20:30:51 +0900
Subject: [PATCH 2/2] =?UTF-8?q?=E3=83=A9=E3=83=B3=E3=82=AD=E3=83=B3?=
 =?UTF-8?q?=E3=82=B0=E3=81=AE=E7=B7=B4=E7=BF=92=E5=95=8F=E9=A1=8C?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 app.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/app.js b/app.js
index c3823f9..a8c78af 100644
--- a/app.js
+++ b/app.js
@@ -34,10 +34,10 @@ rl.on('close', () => {
     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;
   });
-  const rankingStrings = rankingArray.map(([key, value]) => {
-    return `${key}: ${value.popu10}=>${value.popu15} 変化率 ${value.change}`;
+  const rankingStrings = rankingArray.map(([key, value], i) => {
+    return `${i + 1}位 ${key}: ${value.popu10}=>${value.popu15} 変化率 ${value.change}`;
   });
   console.log(rankingStrings);
 });
\ No newline at end of file