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+# Title
+
+## STEP1
+
+### 発想
+
+* 境界を探す問題。境界がないこともありうる。
+  
+### 想定されるユースケース
+
+### 何が分からなかったか?
+
+* 不明点なく進めることができた。
+
+```javascript
+const findMin = function(nums) {
+    // find the index which is a[i - 1] > a[i]. This index might not be found.
+    // left <= target <= right
+    // loop condition is left <= right
+    // break condition is right < left or target is found
+
+    let left = 1
+    let right = nums.length - 1
+    while (left <= right) {
+        const middle = Math.floor((left + right) / 2)
+        console.log(left, right, middle)
+        if (nums[middle] < nums[middle - 1]) {
+            return nums[middle]
+        }
+        if (nums[0] < nums[middle]) {
+            left = middle + 1
+            continue
+        }
+        right = middle - 1
+    }
+    return nums[0]
+};
+```
+
+## STEP2
+
+```javascript
+```
+
+## STEP3
+
+```javascript
+```
+
+## 感想
+
+### コメント集を読んで
+
+## 他の人のPRを読んで
+
+## その他の方法
+
+* (`*1`) 末尾と比較する方法
+
+```javascript
+const findMin = function(nums) {
+    let left = 1
+    let right = nums.length - 1
+    while (left <= right) {
+        const middle = Math.floor((left + right) / 2)
+        if (nums[middle] < nums[middle - 1]) {
+            return nums[middle]
+        }
+        if (nums[middle] < nums[nums.length - 1]) {
+            right = middle - 1
+            continue
+        }
+        left = middle + 1
+    }
+    return nums[0]
+};
+```
+
+### コードの良し悪し
+
+* `*0`
+
+* `*1`
+
+## 調べたこと
+