Binary-Indexed-Tree onhttps://h30306.github.io/blog/zh-tw/tags/binary-indexed-tree/Recent content in Binary-Indexed-Tree onHugo -- gohugo.iozh-twhwork0511@gmail.com (Wei Yi Chung)hwork0511@gmail.com (Wei Yi Chung)© 2026 Wei Yi ChungWed, 21 Oct 2026 00:00:00 +0000Segment Tree 與 Fenwick Treehttps://h30306.github.io/blog/zh-tw/algorithm/segment-tree/Wed, 21 Oct 2026 00:00:00 +0000hwork0511@gmail.com (Wei Yi Chung)https://h30306.github.io/blog/zh-tw/algorithm/segment-tree/單點更新、區間查詢：Fenwick Tree（樹狀陣列）用 i & -i 跳，線段樹用遞迴把區間切兩半；兩者都是每次操作 O(log n)LeetCode 4051: Count Subarrays with Distant Sumshttps://h30306.github.io/blog/zh-tw/leetcode/leetcode-4051/Mon, 19 Oct 2026 00:00:00 +0000hwork0511@gmail.com (Wei Yi Chung)https://h30306.github.io/blog/zh-tw/leetcode/leetcode-4051/LeetCode 4051 解題筆記：前綴和 + 補集 + 區間計數，以及 k = 0 的邊界LeetCode 315: Count of Smaller Numbers After Selfhttps://h30306.github.io/blog/zh-tw/leetcode/leetcode-315/Sun, 18 Oct 2026 00:00:00 +0000hwork0511@gmail.com (Wei Yi Chung)https://h30306.github.io/blog/zh-tw/leetcode/leetcode-315/LeetCode 315 解題筆記：帶 index 的 merge sort，以及 BIT 解法LeetCode 2193: Minimum Number of Moves to Make Palindromehttps://h30306.github.io/blog/zh-tw/leetcode/leetcode-2193/Wed, 02 Sep 2026 00:00:00 +0000hwork0511@gmail.com (Wei Yi Chung)https://h30306.github.io/blog/zh-tw/leetcode/leetcode-2193/LeetCode 2193 解題筆記：貪心處理最外層：拿最後一個字元，把它最左邊的同伴換到最前面，花費是那個位置；落單的字元最後在正中間，花費是它到中間的距離LeetCode 327: Count of Range Sumhttps://h30306.github.io/blog/zh-tw/leetcode/leetcode-327/Sat, 01 Aug 2026 00:00:00 +0000hwork0511@gmail.com (Wei Yi Chung)https://h30306.github.io/blog/zh-tw/leetcode/leetcode-327/LeetCode 327 解題筆記：前綴和 + merge sort 計數，兩個指針卡出區間；重打十幾次的練習紀錄LeetCode 307: Range Sum Query - Mutablehttps://h30306.github.io/blog/zh-tw/leetcode/leetcode-307/Fri, 19 Jun 2026 00:00:00 +0000hwork0511@gmail.com (Wei Yi Chung)https://h30306.github.io/blog/zh-tw/leetcode/leetcode-307/LeetCode 307 解題筆記：單點更新加區間和，前綴和每次更新要 O(n)；用線段樹或 Fenwick Tree，兩種操作都是 O(log n)