{"trustable":false,"prependHtml":"\u003cscript\u003e window.katexOptions \u003d { disable: true }; \u003c/script\u003e\n\u003cscript type\u003d\"text/x-mathjax-config\"\u003e\n MathJax.Hub.Config({\n tex2jax: {\n inlineMath: [[\u0027$$$\u0027,\u0027$$$\u0027], [\u0027$\u0027,\u0027$\u0027]],\n displayMath: [[\u0027$$$$$$\u0027,\u0027$$$$$$\u0027], [\u0027$$\u0027,\u0027$$\u0027]]\n }\n });\n\u003c/script\u003e\n\u003cscript async src\u003d\"https://mathjax.codeforces.org/MathJax.js?config\u003dTeX-AMS-MML_HTMLorMML\" type\u003d\"text/javascript\"\u003e\u003c/script\u003e","sections":[{"title":"","value":{"format":"HTML","content":"\u003cscript type\u003d\u0027text/x-mathjax-config\u0027\u003eMathJax.Hub.Config({tex2jax: { inlineMath: [[\u0027$\u0027,\u0027$\u0027]] } }); \u003c/script\u003e\n\u003cscript type\u003d\u0027text/javascript\u0027 src\u003d\u0027https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.1/MathJax.js?config\u003dTeX-AMS-MML_HTMLorMML\u0027\u003e\u003c/script\u003e\n\u003cscript type\u003d\u0027text/javascript\u0027\u003esetTimeout(function(){MathJax.Hub.Queue([\u0027Typeset\u0027, MathJax.Hub, \u0027left_view\u0027]);}, 2000);\u003c/script\u003e\n\u003cdiv class\u003d\"panel_content\"\u003e\n 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) \n\u003c/div\u003e\n(n)表示欧拉函数,比n小且与n互质的个数。\u003c/br\u003e\n求(a)+(a+1)+...+(b)\u003c/br\u003e\n\n提示:欧拉函数可以通过容斥原理分析得到:\u003cbr\u003e\n如果p1,p2,...,pk是n的质因子,则有:\u003cbr\u003e\n(n)\u003dn*(1-1/p1)*(1-1/p2)*....*(1-1/pk)\u003cbr\u003e\n\n可以在筛素数过程中,得到质因子,并且计算出n的欧拉函数值。\n\n\n"}},{"title":"Input","value":{"format":"HTML","content":"There are several test cases. Each line has two integers a, b (2\u0026lt;a\u0026lt;b\u0026lt;3000000).\u003cbr\u003e\n有多组数据,每组数据两个整数a和b\n"}},{"title":"Output","value":{"format":"HTML","content":"Output the result of (a)+ (a+1)+....+ (b)"}},{"title":"Sample Input","value":{"format":"HTML","content":"\u003cpre\u003e3 100\u003c/pre\u003e"}},{"title":"Sample Output","value":{"format":"HTML","content":"\u003cpre\u003e3042\u003c/pre\u003e"}}]}