Determine whether an integer is a palindrome.
Do this without extra space.if use recursive, like check the first dig and last
dig, then remove them, c...
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其他好文 时间：
2014-05-23 02:45:15
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230
Sum square difference
Problem 6
The sum of the squares of the first ten natural numbers is,
12 + 22 + ... + 102 = 385
The square of the sum of the first ten natural numbers is,
(1 + 2 + ....
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其他好文 时间：
2014-05-23 02:22:57
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193
Smallest multiple
Problem 5
2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder.
What is the smallest positive number that is evenly di...
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其他好文 时间：
2014-05-23 01:51:13
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261
Problem 1: Multiples of 3 and 5
If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.
Find the sum of all the multip...
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其他好文 时间：
2014-05-23 01:43:01
阅读次数：
253
【题目】
Given a collection of numbers, return all possible permutations.
For example,
[1,2,3] have the following permutations:
[1,2,3], [1,3,2], [2,1,3], [2,3,1], [3,1,2], and [3,2,1].
【题意】
给定一个数组，生成所有的全排列
【思路】
递归，类DFS...
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其他好文 时间：
2014-05-23 01:08:26
阅读次数：
194
Problem 2: Even Fibonacci numbers
Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:
1, 2,...
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其他好文 时间：
2014-05-22 23:29:44
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435
马上要去比赛了。
今天做了一下2014北京邀请赛，出了两道题目，感觉很水啊、、、
首先H题：
H. Happy Reversal
Time Limit: 1000ms
Case Time Limit: 1000ms
Memory Limit: 65536KB
64-bit integer IO format: %lld Java class name...
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其他好文 时间：
2014-05-22 23:07:32
阅读次数：
417
Jimmy writes down the decimal representations of all natural numbers between and including m and n, (m ≤ n). How many zeroes will he write down?
Input
Input starts with an integer T (≤ 11000), denot...
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其他好文 时间：
2014-05-22 22:59:18
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354
Problem 4: Largest palindrome product
A palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91 × 99.
Find the largest pal...
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其他好文 时间：
2014-05-22 18:48:46
阅读次数：
355
【题目】
Given a collection of numbers that might contain duplicates, return all possible unique permutations.
For example,
[1,1,2] have the following unique permutations:
[1,1,2], [1,2,1], and [2,1,1].
【题意】
给定一个候选数集合，候选集中可能存在重复数，返回所有的排列
【思路】
...
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其他好文 时间：
2014-05-22 17:32:17
阅读次数：
247
