hunnu11546:Sum of f(x)

【hunnu11546:Sum of f(x)】的更多相关文章

Problem description 令f(x)为x的全部约数之和,x的约数即能够被x整除的数.如f(24)=1+2+3+4+6+8+12+24=60),求 f(l) + f(l + 1) + -- + f(r) Input 第一行为一个整数T(T<=100000),表示数据的组数. 接下来T行,每行有两个整数l.r(1 <= l <= r <= 200000) Output 对每组数据,输出f(l)+f(l+1)+--+f(r) 的和 Sample Input 2…

hunnu Sum of f(x)

http://acm.hunnu.edu.cn/online/?action=problem&type=show&id=11546&courseid=0 Sum of f(x) Time Limit: 1000ms, Special Time Limit:2500ms, Memory Limit:32768KB Total submit users: 196, Accepted users: 118 Problem 11546 : No special judgement Prob…

hnnu 11546 Sum of f(x) （求一个数的全部约数和）

代码: #include<cstdio> #include<cstring> #define N 200000 using namespace std; long long f[N+5]; long long s[N+5]; int main() { s[0]=0; for(int i=1;i<=N;i++) { for(int j=1;j*i<=N;j++) { f[j*i]+=i; } } for(int i=1;i<=N;i++) { s[i]=s[i-1]…

three Sum

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 solut…

hdu 4389 X mod f(x) 数位DP

思路: 每次枚举数字和也就是取模的f(x),这样方便计算. 其他就是基本的数位Dp了. 代码如下: #include<iostream> #include<stdio.h> #include<algorithm> #include<iomanip> #include<cmath> #include<cstring> #include<vector> #define ll __int64 #define pi acos(-1…

geeksforgeeks@ Find sum of different corresponding bits for all pairs (Bit manipulation)

http://www.practice.geeksforgeeks.org/problem-page.php?pid=387 Find sum of different corresponding bits for all pairs We define f (X, Y) as number of different corresponding bits in binary representation of X and Y. For example, f (2, 7) = 2, since b…