Factors of a Number
题号:NC218169
时间限制:C/C++/Rust/Pascal 1秒,其他语言2秒
空间限制:C/C++/Rust/Pascal 256 M,其他语言512 M
64bit IO Format: %lld

题目描述

Define a function d(n), representing the quantity of factors of a positive integer a.
For example, the expression d(12) = 6 representing the number 12 have 6 factors - 1, 2, 3, 4, 6, 12.
Given l, r and k, determine the value of 

输入描述:

Three integers lr and k, separated by space.

输出描述:

The value of the expression.
示例1

输入

复制
1 5 1

输出

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10
示例2

输入

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1 10 2

输出

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48
示例3

输入

复制
1 100 3

输出

复制
2302

备注:

1 <= l, r, k <= 1000