escriptionThenthTriangularnumber,T(n) = 1 + …
+n, is the sum of the firstnintegers. It is the number of points in a triangular
array withnpoints on si...
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其他好文 时间:
2014-05-19 19:50:24
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191
证明:$(1)$设$r\left( A \right) =
r$,则由$Jordan$标准形理论知,存在可逆阵$P$,使得\[{P^{ - 1}}AP = \left(
{\begin{array}{*{20}{c}}0&{{E_r}}\\0&0\end{array}} \right)\]从而可知\...
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其他好文 时间:
2014-05-19 17:59:50
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195
array_shift(使得第一个参数和后面的参数分开,先进先出)vsprintf格式化sql语句$r
=
substr($sql,0,6)从0个开始截取6位。这种写法在php5.4之前是不支持的strcasecmp(a,b);如果a=b就返回0,如果第一个大于第二个就返回1,否则返回-1array...
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Web程序 时间:
2014-05-19 17:52:10
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327
证明:由于${A^2} = A$,且$r\left( A \right) =
r$,则存在可逆阵$P$,使得\[{P^{ - 1}}AP = \left(
{\begin{array}{*{20}{c}}{{E_r}}&{}\\{}&0\end{array}} \right)\]即${P^{ -
1...
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其他好文 时间:
2014-05-19 16:43:52
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208
【题目】
Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly one solution.
For example, given array S = {...
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其他好文 时间:
2014-05-18 10:37:57
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269
【题目】
Given an array S of n integers, are there elements a, b, c, and d in S such that a + b + c + d = target? Find all unique quadruplets in the array which gives the sum of target.
Note:
Elements in a quadruplet (a,b,c,d) must be in non-descending ord...
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其他好文 时间:
2014-05-18 08:46:04
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227
Point pos(100, 100); //start point
m_animSprite->setPosition(pos);
int count = 8; float radius = 50.f; float angle = 360.f/count; auto array = PointArray::create(count + 1); Point pt0(r...
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其他好文 时间:
2014-05-18 07:02:31
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250
3SumClosest
Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exactly one solution....
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其他好文 时间:
2014-05-18 05:57:48
阅读次数:
244
【题目】
Write a function to find the longest common prefix string amongst an array of strings.
【题意】
求一组字符串的最长公共前缀
【思路】
使用归并思想求解
要求字符串[1,2,..,k,k+1,...n]的最大公共前缀,先分别求[1,2,...k]和[k+1,...,n]的公共前缀...
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其他好文 时间:
2014-05-18 05:17:53
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232
【题目】
Given an array S of n integers, are there elements a, b, c in S such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero.
Note:
Elements in a triplet (a,b,c) must be in non-descending order. (ie, a ≤ b ≤ c)
The so...
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其他好文 时间:
2014-05-18 03:15:50
阅读次数:
287