题目链接:http://lightoj.com/volume_showproblem.php?problem=1234 给你一个数n,让你求 这个要是直接算的话肯定TLE,要是用1e8的数组预处理存储答案也一定MLE. 所以我用1e6的数组存储每100个数的答案,然后每次给你n的时候顶多算99次. #include <iostream> #include <cstdio> #include <cstring> using namespace std; const int…

先举个例子,假如给你的数是100的话,将100/2=50;是不是就是100除100-51之间的数取整为1: 100/3=33;100除50到34之间的数为2,那么这样下去到sqrt(100);就可以求得100除以sqrt(100)+1到100之间数的和,也就是后90项的和以求得. 剩余的前10项直接代公式求就行了. 复杂度为2*sqrt(N); http://lightoj.com/volume_showproblem.php?problem=1245 1 #include<stdio.h>…

http://lightoj.com/volume_showproblem.php?problem=1234 Harmonic Number Time Limit:3000MS     Memory Limit:32768KB     64bit IO Format:%lld & %llu Submit Status Practice LightOJ 1234 Description In mathematics, the nth harmonic number is the sum of th…

D - Harmonic Number Time Limit:3000MS     Memory Limit:32768KB     64bit IO Format:%lld & %llu Submit Status Practice LightOJ 1234 Description In mathematics, the nth harmonic number is the sum of the reciprocals of the first n natural numbers: In th…

Harmonic Number Time Limit:3000MS     Memory Limit:32768KB     64bit IO Format:%lld & %llu Submit Status Practice LightOJ 1234 Description In mathematics, the nth harmonic number is the sum of the reciprocals of the first n natural numbers: In this p…

题目链接:http://lightoj.com/volume_showproblem.php?problem=1234 Sample Input Sample Output Case : Case : 1.5 Case : 1.8333333333 Case : 2.0833333333 Case : 2.2833333333 Case : 2.450 Case : 2.5928571429 Case : 2.7178571429 Case : 2.8289682540 Case : 18.89…

Harmonic Number In mathematics, the nth harmonic number is the sum of the reciprocals of the first n natural numbers: In this problem, you are given n, you have to find Hn. Input Input starts with an integer T (≤ 10000), denoting the number of test c…

http://lightoj.com/volume_showproblem.php?problem=1245 G - Harmonic Number (II) Time Limit:3000MS     Memory Limit:32768KB     64bit IO Format:%lld & %llu Submit Status Practice LightOJ 1245 Description I was trying to solve problem '1234 - Harmonic…

1245 - Harmonic Number (II)   PDF (English) Statistics Forum Time Limit: 3 second(s) Memory Limit: 32 MB I was trying to solve problem '1234 - Harmonic Number', I wrote the following code long long H( int n ) {     long long res = 0;     for( int i =…

题目链接:https://vjudge.net/problem/LightOJ-1245 1245 - Harmonic Number (II)    PDF (English) Statistics Forum Time Limit: 3 second(s) Memory Limit: 32 MB I was trying to solve problem '1234 - Harmonic Number', I wrote the following code long long H( int…