UVa 10892 - LCM Cardinality
2016-02-16
题目地址
描述 给定正整数 n ( 1 ≤ n ≤ 2 0 0 0 0 0 0 0 0 0 ) n(1\le n\le 2000000000) n ( 1 ≤ n ≤ 2 0 0 0 0 0 0 0 0 0 ) ,统计有多少个整数对 ( a , b ) (......