ZUFEOJ Home ProblemSet Source/Category Contest Status Ranklist F.A.Qs
Login Register

4940: Sum of Remainders

内存限制：256 MB 时间限制：2 S 标准输入输出
题目类型：传统 评测方式：文本比较 上传者：
提交：1 通过：1
提交提交记录统计Web Board

题目描述

E. Sum of Remainders
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output
Calculate the value of the sum: n mod 1 + n mod 2 + n mod 3 + ... + n mod m. As the result can be very large, you should print the value modulo 109+7 (the remainder when divided by 109+7).
The modulo operator a mod b stands for the remainder after dividing a by b. For example 10 mod 3 = 1.
Input
The only line contains two integers n,m (1≤n,m≤1013) − the parameters of the sum.
Output
Print integer s − the value of the required sum modulo 109+7.
Examples
Input 
3 4
Output 
4
Input 
4 4
Output 
1
Input 
1 1
Output 
0

输入样例 复制

输出样例 复制

分类标签