ACM思维题训练集合 The Little Elephant has two permutations a and b of length n, consisting of numbers from 1 to n, inclusive. Let’s denote the i-th (1 ≤ i ≤ n) elemen...

You are given an array consisting of n non-negative integers a 1, a 2, …, a n.

Given a permutation p of length n, find its subsequence s1, s2, …, sk of length at least 2 such that:

You are given a permutation of length n. Recall that the permutation is an array consisting of n distinct integers from 1 to n in arbitrary order. For example, ...

Notice that the number 123456789 is a 9-digit number consisting exactly the numbers from 1 to 9, with no duplication. Double it we will obtain 246913578, which ...

Mrs. Smith is trying to contact her husband, John Smith, but she forgot the secret phone number!

An array of integers p1,p2,…,pnp1,p2,…,pn is called a permutation if it contains each number from 11 to nn exactly once. For example, the following arrays are p...

The set [1,2,3,...,_n_] contains a total of n! unique permutations.

1001 Add More Zero（签到题）题目链接 HDU6033 Add More Zeroimage.png#include <cstdio>#include <cmath>int cas,m;int main(){while(~scanf("%d",&m)){printf("Case #......

Mantel test计算的是两个不相似矩阵之间的相关性。生态学上的意义是验证环境相似的地方是否物种也相似；环境不相似的地方物种是否不相似。计算方法为Ecodist包中mantel函数。输入的两个矩阵分别为群落OTU及环境因子/地...