# 归档 2016年9月

## 题目描述：

LeetCode 400. Nth Digit

Find the nth digit of the infinite integer sequence 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, ...

Note:
n is positive and will fit within the range of a 32-bit signed ...

## LeetCode Weekly Contest 4解题报告 作者是 在线疯狂 发布于 2016年9月11日 在 LeetCode.

LeetCode Weekly Contest 4是LeetCode举办的第三场正式周赛，共4道题目，比赛时长2.5小时。

LeetCode 396. Rotate Function

LeetCode 397. Integer Replacement

LeetCode 398. Random Pick Index

LeetCode 399. Evaluate Division

## 题目描述：

LeetCode 399. Evaluate Division

p> Equations are given in the format `A / B = k`, where `A` and `B` are variables represented as strings, and `k` is a real number (floating point number). Given some queries, return the answers. If ...

## 题目描述：

LeetCode 398. Random Pick Index

Given an array of integers with possible duplicates, randomly output the index of a given target number. You can assume that the given target number must exist in the array.

Note:
The array size ...

## 题目描述：

LeetCode 397. Integer Replacement

Given a positive integer n and you can do operations as follow:

1. If n is even, replace n with `n/2`.
2. If n is odd, you can replace n with either `n + 1` or `n ...`