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flash_7's blog

By flash_7, history, 3 years ago, In English,

Given a number N we have to find the summation of all possible LCM(i,j) where i <= j <= N.

Constraints: N<=10^6 and total test case <= 10^5

Problem Link : Light OJ 1375

 
 
 
 
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3 years ago, # |
  Vote: I like it +16 Vote: I do not like it

Use the explanation of this problem as a hint: http://blog.forthright48.com/2015/08/spoj-lcmsum-lcm-sum.html

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    3 years ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    Thank you so much :) Sam vai already wrote about this didn't notice earlier :P