From 1d070b8932b6a3c7b644ca2a6f4d9f61d87115a4 Mon Sep 17 00:00:00 2001
From: yko-git <yko.iwata@gmail.com>
Date: Wed, 13 Mar 2024 14:55:21 +0900
Subject: [PATCH] fix 002_search binarySearch

---
 004_algorithm/002_search.js | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/004_algorithm/002_search.js b/004_algorithm/002_search.js
index a54c533..5e73518 100644
--- a/004_algorithm/002_search.js
+++ b/004_algorithm/002_search.js
@@ -31,18 +31,20 @@ function linearSearch(array, target) {
 
 function binarySearch(array, target) {
   // 配列の位置を設定
+  let index = -1;
   let low = 0; //左端
   let high = array.length - 1; //右端
 
   //左端が右端以下の間（1つの要素に絞られるまで）は処理を続ける
   while (low <= high) {
-    mid = low + high; // 真ん中の位置
-    guess = array[mid]; // 真ん中の要素
+    let mid = Math.floor((low + high) / 2); // 真ん中の位置
+    let guess = array[mid]; // 真ん中の要素
 
     //真ん中の要素がtargetと合致したら
     if (guess == target) {
       //位置を返す
-      return mid;
+      index = mid;
+      return index;
 
       //真ん中の要素がtargetより大きかったら
     } else if (guess > target) {
@@ -52,7 +54,7 @@ function binarySearch(array, target) {
       low = mid + 1;
     }
   }
-  return -1;
+  return index;
 }
 
 module.exports = {