Home This is the blog of Chao Xu. Recent Posts Represent an element in a free monoid with minimum weight 2013-03-26 Regular expression for a interval of non-negative integers 2013-03-21 A Data Structure Reduction 2013-02-04 There exist a path of length \(\lceil d(G)\rceil\) for every graph \(G\) 2013-01-30 Number of ways to make change 2012-08-31 Basis of the module \(\Z^n\) 2012-08-30 A relation between \(L_\infty\) metric and \(L_1\) metric in \(\R^2\) 2012-08-23 Maximize the area of a radar chart 2012-08-08 A cute theorem involving xor 2012-06-19 Proof that binomial coefficients are integers 2012-04-23 See More...