UVA_11526 H(n)

思路就是找到n/i结果相同的，跳过并累加
注意的是数据十分变态，居然还有n<0的数。。。无语。。。数据量也是大的吓人....

ProblemG[/b]

H(n)[/b]

Input:[/b]StandardInput

Output:[/b]StandardOutput

WhatisthevaluethissimpleC++functionwill
return?

longlongH(intn){

longlong
res=0;

for(inti
=1;i<=n;i=i+1){

res=
(res+n/i);

}

return
res;

}

Input

ThefirstlineofinputisanintegerT(T<=1000)
thatindicatesthenumberoftestcases.EachofthenextTlinewillcontaina
singlesigned32bitintegern.

Output

Foreachtestcase,outputwillbeasinglelinecontainingH(n).

SampleInputOutputforSampleInput

2 5 10

10 27

Problem-setter:Md.ArifuzzamanArif

SpecialThanks:ShahriarManzoor

#include<iostream>
#include<cmath>
usingnamespacestd;
longlongH(longlongn){

if(n<=0)return0;
longlongres=n;
longlongi,pre=n,tmp;
for(i=2;i<=n;i++)
{
res+=(tmp=n/i);
if(tmp!=pre)
{
res+=(n/tmp-i)*(tmp);
i=n/tmp;
pre=tmp;
}

}
returnres;
}
intmain()
{
longlongn,t;
cin>>t;
while(t--)cin>>n,cout<<H(n)<<endl;
return0;
}