http://scottsievert.github.io/blog/2015/01/31/the-mysterious-eigenvalue/ The Fibonacci problem is a well known mathematical problem that models population growth and was conceived in the 1200s. Leonardo of Pisa aka Fibonacci decided to use a recursiv…
vThere are three ways to solve Fibonacci problem Recursion Memoize Bottom-up 'First Recursion approach: def fib(n): or n == : result = else: result = fib(n-) + fib(n -) return result; As we can see to calculate fib(5), we need to calculate fib(3) twi…
Codeforces 题面传送门 & 洛谷题面传送门 一道名副其实(beautiful)的结论题. 首先看到这道设问方式我们可以很自然地想到套用斐波那契数列的恒等式,注意到这里涉及到 \(F_{a+id}\),因此考虑斐波那契数列组合恒等式 \(F_{m+n+1}=F_mF_{n}+F_{m+1}F_{n+1}\),具体证明戳这里,这里就不再赘述了. 注意到此题还涉及后 \(18\) 位,也就是要将斐波那契数列的各种运算放到模 \(10^{18}\) 意义下进行,因此我们可以考虑找一下斐波那契数…
Fibonacci Problem Description 2007年到来了.经过2006年一年的修炼,数学神童zouyu终于把0到的Fibonacci数列(f[0]=0,f[1]=1;f[i] = f[i-1]+f[i-2](i>=2))的值全部给背了下来.接下来,CodeStar决定要考考他,于是每问他一个数字,他就要把答案说出来,不过有的数字太长了.所以规定超过4位的只要说出前4位就可以了,可是CodeStar自己又记不住.于是他决定编写一个程序来测验zouyu说的是否正确.   Inpu…
Description Without expecting, Angel replied quickly.She says: "I'v heard that you'r a very clever boy. So if you wanna me be your GF, you should solve the problem called GF~. " How good an opportunity that Gardon can not give up! The "Prob…
Gauss Fibonacci Time Limit: 3000/1000 MS (Java/Others)     Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 27    Accepted Submission(s): 5 Problem Description Without expecting, Angel replied quickly.She says: "I'v heard that you'r a ve…
http://acm.hdu.edu.cn/showproblem.php?pid=1588 Problem Description Without expecting, Angel replied quickly.She says: "I'v heard that you'r a very clever boy. So if you wanna me be your GF, you should solve the problem called GF~. " How good an…
Revenge of Fibonacci Problem Description The well-known Fibonacci sequence is defined as following: Here we regard n as the index of the Fibonacci number F(n).  This sequence has been studied since the publication of Fibonacci's book Liber Abaci. So…
在实际工作中,std的string功能相对于MFC的CString来说,实在是相形见绌. CStdString类实现了CString的功能,支持跨平台. // ============================================================================= // FILE: StdString.h // AUTHOR: Joe O'Leary (with outside help noted in comments) // // If y…
Question Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. Solution 1 -- Recursion Problems related with tree can always be solved by recurs…