/*题意：(n)表示小于n与n互质的数有多少个，给你两个数a，b让你计算a+(a+1)+(a+2)+......+b;初步思路：暴力搞一下，打表#放弃：打了十几分钟没打完#改进：欧拉函数：具体证明看po主的博客 ^0^#超时：这里直接用欧拉函数暴力搞还是不可以的,用到线性筛欧拉函数，这里总和爆int，要用long long*/#include
         
          #define ll long longusing namespace std;/**************************欧拉函数模板*****************************///筛选法打欧拉函数表 #define Max 3000010int euler[Max];void Init(){      euler[1]=1;     for(int i=2;i
         

 

The Euler function

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)

Total Submission(s): 224 Accepted Submission(s): 124

Problem Description

The Euler function phi is an important kind of function in number theory, (n) represents the amount of the numbers which are smaller than n and coprime to n, and this function has a lot of beautiful characteristics. Here comes a very easy question: suppose you are given a, b, try to calculate (a)+ (a+1)+....+ (b)

 

Input

There are several test cases. Each line has two integers a, b (2<a<b<3000000).

 

Output

            Output the result of  (a)+ (a+1)+....+ (b)

 

Sample Input

3 100

 

Sample Output

3042

 

Source

2009 Multi-University Training Contest 1 - Host by TJU

 

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