OPMODULO  "Operation  Modulo"
Mahmud solved some easy math problems from SPOJ and called himself king of number theory. GodFather GodMATHer Rashad heard it and got angry, so he kidnapped Mahmud. Rashad gave him a task called "Operation  Modulo". Mahmud must solve this task, you know what will happen otherwise ;(. In the Operation  Modulo, we define a function f(n) = (n mod 1) + (n mod 2) + (n mod 3) + ... + (n mod n), where n mod x donates the remainder when dividing n by x. Rashad interests with integers n such that f(n)=f(n1), so he gave Mahmud two numbers L and R, and demands him to find the sum of all integers n such that L ≤ n ≤ R and f(n)=f(n1).
Input
First and the only line of input contains two positive integers, L and R (1 ≤ L ≤ R ≤ 10^{18}).
Output
Print the demanded sum in one line.
Example
Input:
1 3
Output:
3
Note:
I hope you proved your solution before submitting it :)
hide comments
hodobox:
20190526 03:19:35
@drdrunkenstein, so you see that f(1)=f(0) and f(2)=f(1), so both n=1 and n=2 satisfy f(n)=f(n1), and the answer is the sum of all such numbers, in this case 1+2 = 3. 

drdrunkenstein:
20190424 16:58:39
Can someone explain me the test cases?


sandeep48:
20181225 15:01:15
try to figure out the sequence of no.


kushagrasri:
20181113 08:04:20
once you get the idea, the problem is super easy.


abhishak69:
20181006 13:59:40
can you give more testcase


prakash1108:
20180317 14:22:10
nice problem @barishnamazov


julkas:
20180317 10:58:21
@barishnamazov Good problem, Успехов!


mahmud2690:
20180315 19:50:30
nice problem bratan. +1

Added by:  Barish 
Date:  20180315 
Time limit:  1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All 
Resource:  Deep places of my brain 