Harry is a Junior middle student. He is very interested in the story told by his mathematics teacher about the Yang Hui triangle in the class yesterday. After class he wrote the following numbers to s...
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其他好文 时间：
2014-08-29 14:42:38
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275
http://poj.org/problem?id=3252题意：问从a到b有多少个round number。如果某数的二进制表示中0的个数不少于1的个数，那么它就是一个round number。分析：数位dp。就我目前碰到的几道数位dp来说，其实所谓数位dp，就是和组合数有联系的递推罢了。还是转换...
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其他好文 时间：
2014-08-28 19:45:55
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232
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].
思...
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其他好文 时间：
2014-08-28 14:52:49
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158
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].
...
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其他好文 时间：
2014-08-28 14:51:19
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148
Let's consider a triangle of numbers in which a number appears in the first line, two numbers appear in the second line, three in the third line, etc....
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其他好文 时间：
2014-08-28 13:03:29
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218
Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers.
If such arrangement is not possible, it must rearrange it as the lowest possible o...
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其他好文 时间：
2014-08-28 11:34:29
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241
Phone ListCrawling in process...
Crawling failed
Time Limit:1000MS
Memory Limit:32768KB 64bit IO Format:%I64d & %I64u
Submit
Status
Description
Given a list of phone numbers,...
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其他好文 时间：
2014-08-28 11:27:49
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168
200:
Problem Statement
Computers tend to store dates and times as single numbers which represent the number of seconds or milliseconds since a particular date. Your task in this ...
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其他好文 时间：
2014-08-28 11:27:29
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244
Given a collection of numbers that might contain duplicates, return all possible unique permutations.For example,[1,1,2] have the following unique per...
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其他好文 时间：
2014-08-27 21:55:38
阅读次数：
242
http://poj.org/problem?id=3252
"Round Number "被称为其二进制形式中0的个数比1的个数多。求[x,y]区间内“Round Number”的个数。
计数的时候最重要的是处理前导零，前导零不算数，因此与SCOI2009一样，增加一个标记变量first，标志着当前这意味是不是首位，不是首位的话1和0的个数都为0，否则根据枚举的1或0进行记忆...
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其他好文 时间：
2014-08-27 20:36:48
阅读次数：
211
