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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#432946#8761. 另一个计数问题qzezTL 6ms18084kbC++142.3kb2024-06-07 21:04:482024-06-07 21:04:49

Judging History

你现在查看的是最新测评结果

  • [2024-06-07 21:04:49]
  • 评测
  • 测评结果:TL
  • 用时:6ms
  • 内存:18084kb
  • [2024-06-07 21:04:48]
  • 提交

answer

#include<bits/stdc++.h>
using namespace std;
#ifdef DEBUG
#include"debug.h"
#else
#define debug(...) void()
#endif
#define all(x) (x).begin(),(x).end()
template<class T>
auto ary(T *a,int l,int r){
	return vector<T>{a+l,a+1+r};
}
using ll=long long;
using ull=unsigned ll;
const int N=sqrt(1e11)+5,M=N*2,mod=998244353;
ll n;
struct node{
	int x,y;
	node(int a=0,int b=0):x(a),y(b){}
};
#ifdef DEBUG
ostream& operator << (ostream &out,node a){
	return out<<make_pair(a.x,a.y);
}
#endif
node operator + (const node &a,const node &b){
	return node((a.x+b.x)%mod,(a.y+b.y)%mod);
}
node operator - (const node &a,const node &b){
	return node((a.x+mod-b.x)%mod,(a.y+mod-b.y)%mod);
}
node operator * (const node &a,const node &b){
	return node(1ll*a.x*b.x%mod,1ll*a.y*b.y%mod);
}
int cnt,pri[N],vis[N];
node pre[N];
void init(int n){
	fill(vis,vis+1+n,0),cnt=0;
	for(int i=2;i<=n;i++){
		pre[i]=pre[i-1];
		if(!vis[i]){
			pri[++cnt]=i;
			pre[i]=pre[i]+node(i,1ll*i*i%mod);
		}
		for(int j=1;j<=cnt&&i*pri[j]<=n;j++){
			vis[i*pri[j]]=1;
			if(i%pri[j]==0)break;
		}
	}
}
node f[M];
ll val[M];
int k,id1[N],id2[N];
int getid(ll x){
	if(x<=n/x)return id1[x];
	else return id2[n/x];
}
int sum1(ll x){
	x%=mod;
	return x*(x+1)/2%mod;
}
int sum2(ll x){
	x%=mod;
	return x*(x+1)%mod*(x+x+1)%mod*((mod+1)/6)%mod;
}
node calc(ll n){
	::n=n;
	if(!n)return node();
	init(sqrtl(n)),k=0;
	for(ll l=1,r;l<=n;l=r+1){
		r=n/(n/l);
		ll x=n/l;
		if(x<=n/x)val[id1[x]=++k]=x;
		else val[id2[n/x]=++k]=x;
	}
	for(int i=1;i<=k;i++)f[i]=node(sum1(val[i])-1,sum2(val[i])-1);
	// debug(ary(val,1,k));
	// debug(ary(f,1,k));
	// debug(cnt,ary(pri,1,cnt));
	for(int i=1;i<=cnt;i++){
		node x=node(pri[i],1ll*pri[i]*pri[i]%mod);
		for(int j=1;j<=k&&val[j]>=pri[i];j++){
			f[j]=f[j]-x*f[getid(val[j]/pri[i])]+x*pre[min<ll>(pri[i-1],val[j]/pri[i])];
		}
		// debug(ary(f,1,k),x,pre[pri[i]-1],pri[i]-1);
	}
	// debug("calc",n,f[getid(n)]);
	return f[getid(n)];
}
int main(){
	ll n;
	cin>>n;
	// debug(n,getid(n));
	// debug(f[getid(n)]);
	node res=calc(n)-calc(n/2);
	int sum=(sum1(n)-1-res.x+mod)%mod;
	int ans=(sum2(n)-1-res.y+mod)%mod;
	ans=(1ll*sum*sum+mod-ans)%mod*((mod+1)/2)%mod;
	cout<<ans<<endl;
	return 0;
}
#ifdef DEBUG
#include"debug.hpp"
#endif

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 2ms
memory: 18084kb

input:

4

output:

8

result:

ok 1 number(s): "8"

Test #2:

score: 0
Accepted
time: 0ms
memory: 15924kb

input:

5

output:

8

result:

ok 1 number(s): "8"

Test #3:

score: 0
Accepted
time: 0ms
memory: 15944kb

input:

6

output:

80

result:

ok 1 number(s): "80"

Test #4:

score: 0
Accepted
time: 2ms
memory: 15904kb

input:

7

output:

80

result:

ok 1 number(s): "80"

Test #5:

score: 0
Accepted
time: 0ms
memory: 13808kb

input:

8

output:

200

result:

ok 1 number(s): "200"

Test #6:

score: 0
Accepted
time: 2ms
memory: 15900kb

input:

9

output:

407

result:

ok 1 number(s): "407"

Test #7:

score: 0
Accepted
time: 0ms
memory: 15932kb

input:

10

output:

937

result:

ok 1 number(s): "937"

Test #8:

score: 0
Accepted
time: 2ms
memory: 15912kb

input:

79

output:

3224298

result:

ok 1 number(s): "3224298"

Test #9:

score: 0
Accepted
time: 2ms
memory: 15992kb

input:

123

output:

21077222

result:

ok 1 number(s): "21077222"

Test #10:

score: 0
Accepted
time: 2ms
memory: 18020kb

input:

158

output:

57411585

result:

ok 1 number(s): "57411585"

Test #11:

score: 0
Accepted
time: 0ms
memory: 15788kb

input:

285

output:

605750829

result:

ok 1 number(s): "605750829"

Test #12:

score: 0
Accepted
time: 2ms
memory: 15920kb

input:

355

output:

509863120

result:

ok 1 number(s): "509863120"

Test #13:

score: 0
Accepted
time: 2ms
memory: 17952kb

input:

484

output:

311440260

result:

ok 1 number(s): "311440260"

Test #14:

score: 0
Accepted
time: 3ms
memory: 15992kb

input:

520

output:

102191845

result:

ok 1 number(s): "102191845"

Test #15:

score: 0
Accepted
time: 0ms
memory: 15924kb

input:

706

output:

300787918

result:

ok 1 number(s): "300787918"

Test #16:

score: 0
Accepted
time: 0ms
memory: 16004kb

input:

747

output:

505062591

result:

ok 1 number(s): "505062591"

Test #17:

score: 0
Accepted
time: 0ms
memory: 15912kb

input:

784

output:

181810798

result:

ok 1 number(s): "181810798"

Test #18:

score: 0
Accepted
time: 0ms
memory: 17988kb

input:

76879

output:

716166793

result:

ok 1 number(s): "716166793"

Test #19:

score: 0
Accepted
time: 0ms
memory: 15916kb

input:

209295

output:

753032272

result:

ok 1 number(s): "753032272"

Test #20:

score: 0
Accepted
time: 0ms
memory: 15956kb

input:

220895

output:

874612082

result:

ok 1 number(s): "874612082"

Test #21:

score: 0
Accepted
time: 3ms
memory: 15924kb

input:

243390

output:

68635874

result:

ok 1 number(s): "68635874"

Test #22:

score: 0
Accepted
time: 2ms
memory: 16004kb

input:

414767

output:

862578797

result:

ok 1 number(s): "862578797"

Test #23:

score: 0
Accepted
time: 2ms
memory: 15972kb

input:

431662

output:

231728766

result:

ok 1 number(s): "231728766"

Test #24:

score: 0
Accepted
time: 0ms
memory: 15864kb

input:

521130

output:

106207351

result:

ok 1 number(s): "106207351"

Test #25:

score: 0
Accepted
time: 3ms
memory: 15948kb

input:

668419

output:

580625063

result:

ok 1 number(s): "580625063"

Test #26:

score: 0
Accepted
time: 3ms
memory: 15928kb

input:

700378

output:

790849562

result:

ok 1 number(s): "790849562"

Test #27:

score: 0
Accepted
time: 6ms
memory: 17928kb

input:

965876

output:

856082142

result:

ok 1 number(s): "856082142"

Test #28:

score: -100
Time Limit Exceeded

input:

998244350

output:


result: