Problem Description OO has got a array A of size n ,defined a function f(l,r) represent the number of i (l<=i<=r) , that there's no j(l<=j<=r,j<>i) satisfy ai mod aj=0,now OO want to know ∑i=1n∑j=inf(i,j) mod (109+7).   Input There are m…

 HDU 5288 OO’s Sequence http://acm.hdu.edu.cn/showproblem.php?pid=5288 OO has got a array A of size n ,defined a function f(l,r) represent the number of i (l<=i<=r) , that there’s no j(l<=j<=r,j<>i) satisfy a i mod a j=0,now OO want to k…

题目链接:http://acm.hdu.edu.cn/showproblem.php? pid=5288 题面: OO's Sequence Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others) Total Submission(s): 985    Accepted Submission(s): 375 Problem Description OO has got a arra…

OO's Sequence 题目连接: http://acm.hdu.edu.cn/showproblem.php?pid=5288 Description OO has got a array A of size n ,defined a function f(l,r) represent the number of i (l<=i<=r) , that there's no j(l<=j<=r,j<>i) satisfy ai mod aj=0,now OO wan…

OO’s Sequence Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others)Total Submission(s): 1549    Accepted Submission(s): 559 Problem Description OO has got a array A of size n ,defined a function f(l,r) represent the nu…

OO's Sequence                                                          Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others)                                                                                             T…

OO's Sequence Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 131072/131072 K (Java/Others) Total Submission(s): 1751    Accepted Submission(s): 632 Problem Description OO has got a array A of size n ,defined a function f(l,r) represent the n…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=5288 题意:在闭区间[l,r]内有一个数a[i],a[i]不能整除 除去自身以外的其他的数,f(l,r)表示在这区间内a[i]这样的数的个数,,现给你n个数,求所有区间的f(l,r)的和. 思路:对于每个数a[i]求出他的左右侧最靠近他的且是他的因子的位置L.R,并记录,那么对于每个数a[i]都有了他的L,R,而对于每个a[i]在f(l,r)有价值的次数之和就是(i-L+1)*(R-i+1) 代码:…

Problem Description OO has got a array A of size n ,defined a function f(l,r) represent the number of i (l<=i<=r) , that there's no j(l<=j<=r,j<>i) satisfy ai mod aj=0,now OO want to know ∑i=1n∑j=inf(i,j) mod (+). Input There are multipl…

题意:给一个序列,函数f(l, r)表示在[l, r]区间内有多少数字不是其他数字的倍数,求所有区间的f(l, r)之和. 解法:第一次打多校……心里还有点小激动……然而一道签到题做了俩点……呜呜呜……今天的题还算简单……明天就更难了……写个题解纪念一下多校…… 对于序列中的每一个数,要找到从它的位置起向左右找最远连续不能被它整除的数的位置设为l和r,这个数的位置为pos,答案就是(pos - l + 1) * (r - pos + 1),只要分析一下样例就可以得到这个式子……然后为了找到l和r…