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ID	题目	提交者	结果	用时	内存	语言	文件大小	提交时间	测评时间
#396218	#5406. 随机游走	chenyitaoooo	100 ✓	478ms	82076kb	C++14	679b	2024-04-22 15:24:17	2024-04-22 15:24:19

Judging History

你现在查看的是最新测评结果

[2024-04-22 15:24:19]
评测

测评结果：100
用时：478ms
内存：82076kb

查看

[2024-04-22 15:24:17]
提交

answer

#include<bits/stdc++.h>
#define LL long long 
#define Ri register LL
const LL mo=1e9+7;
using namespace std;
inline LL ksm(LL x,LL y){
	LL res=1;
	while(y>0){
		if(y&1) res=res*x%mo;
		x=x*x%mo;
		y>>=1;
	}
	return res;
}
const int N=1e7+5;
LL n,inv[N],ans;
inline void upd(LL &x,LL y){
	x+=y;
	if(x>=mo) x-=mo;
}
int main(){
	scanf("%d",&n);
	LL o=1;
	for(Ri i=1; i<=2*n; ++i) o=o*i%mo;
	o=ksm(o,mo-2);
	inv[2*n]=o,inv[0]=1;
	for(LL i=2*n-1; i>=1; --i) inv[i]=inv[i+1]*(i+1)%mo;
	for(Ri i=0; i<n; ++i){
		LL o=inv[i]*inv[2*n-i]%mo*ksm(n-i,2*n+1)%mo;
		if(i&1) ans-=o;
		else ans+=o;
	}
	printf("%lld\n",(ans%mo+mo)%mo*2%mo*ksm(2*n+1,mo-2)%mo);
}

源文件, 语言: C++14

详细

Subtask #1:

score: 5

Accepted

Test #1:

score: 5

Accepted

time: 1ms

memory: 3904kb

input:

output:

333333336

result:

ok 1 number(s): "333333336"

Test #2:

score: 5

Accepted

time: 0ms

memory: 3904kb

input:

output:

266666669

result:

ok 1 number(s): "266666669"

Test #3:

score: 5

Accepted

time: 0ms

memory: 3892kb

input:

output:

769047625

result:

ok 1 number(s): "769047625"

Subtask #2:

score: 10

Accepted

Test #4:

score: 10

Accepted

time: 0ms

memory: 3856kb

input:

output:

877865968

result:

ok 1 number(s): "877865968"

Test #5:

score: 10

Accepted

time: 1ms

memory: 3956kb

input:

output:

733342859

result:

ok 1 number(s): "733342859"

Test #6:

score: 10

Accepted

time: 0ms

memory: 3832kb

input:

output:

655899114

result:

ok 1 number(s): "655899114"

Test #7:

score: 10

Accepted

time: 0ms

memory: 3904kb

input:

output:

946326757

result:

ok 1 number(s): "946326757"

Test #8:

score: 10

Accepted

time: 0ms

memory: 3900kb

input:

output:

230714822

result:

ok 1 number(s): "230714822"

Test #9:

score: 10

Accepted

time: 0ms

memory: 3920kb

input:

output:

782967541

result:

ok 1 number(s): "782967541"

Test #10:

score: 10

Accepted

time: 0ms

memory: 3776kb

input:

output:

732371611

result:

ok 1 number(s): "732371611"

Subtask #3:

score: 10

Accepted

Test #11:

score: 10

Accepted

time: 0ms

memory: 3912kb

input:

output:

677123472

result:

ok 1 number(s): "677123472"

Test #12:

score: 10

Accepted

time: 0ms

memory: 3772kb

input:

output:

168974634

result:

ok 1 number(s): "168974634"

Test #13:

score: 10

Accepted

time: 0ms

memory: 3908kb

input:

output:

213343876

result:

ok 1 number(s): "213343876"

Test #14:

score: 10

Accepted

time: 0ms

memory: 3828kb

input:

output:

631124616

result:

ok 1 number(s): "631124616"

Subtask #4:

score: 15

Accepted

Test #15:

score: 15

Accepted

time: 0ms

memory: 3916kb

input:

output:

349256161

result:

ok 1 number(s): "349256161"

Test #16:

score: 15

Accepted

time: 1ms

memory: 3776kb

input:

output:

351095881

result:

ok 1 number(s): "351095881"

Test #17:

score: 15

Accepted

time: 0ms

memory: 3744kb

input:

output:

895504391

result:

ok 1 number(s): "895504391"

Test #18:

score: 15

Accepted

time: 0ms

memory: 3868kb

input:

output:

923555376

result:

ok 1 number(s): "923555376"

Test #19:

score: 15

Accepted

time: 0ms

memory: 3896kb

input:

output:

512220517

result:

ok 1 number(s): "512220517"

Subtask #5:

score: 15

Accepted

Test #20:

score: 15

Accepted

time: 0ms

memory: 3960kb

input:

output:

255062346

result:

ok 1 number(s): "255062346"

Test #21:

score: 15

Accepted

time: 1ms

memory: 6020kb

input:

output:

735041605

result:

ok 1 number(s): "735041605"

Test #22:

score: 15

Accepted

time: 1ms

memory: 3988kb

input:

output:

208261384

result:

ok 1 number(s): "208261384"

Test #23:

score: 15

Accepted

time: 1ms

memory: 3944kb

input:

output:

875427987

result:

ok 1 number(s): "875427987"

Test #24:

score: 15

Accepted

time: 1ms

memory: 3984kb

input:

output:

571776252

result:

ok 1 number(s): "571776252"

Test #25:

score: 15

Accepted

time: 0ms

memory: 3940kb

input:

output:

12983695

result:

ok 1 number(s): "12983695"

Subtask #6:

score: 15

Accepted

Test #26:

score: 15

Accepted

time: 0ms

memory: 3828kb

input:

output:

977435333

result:

ok 1 number(s): "977435333"

Test #27:

score: 15

Accepted

time: 5ms

memory: 4940kb

input:

output:

312666196

result:

ok 1 number(s): "312666196"

Test #28:

score: 15

Accepted

time: 14ms

memory: 8088kb

input:

output:

163767254

result:

ok 1 number(s): "163767254"

Test #29:

score: 15

Accepted

time: 16ms

memory: 7688kb

input:

output:

911833524

result:

ok 1 number(s): "911833524"

Test #30:

score: 15

Accepted

time: 16ms

memory: 7272kb

input:

output:

910277128

result:

ok 1 number(s): "910277128"

Test #31:

score: 15

Accepted

time: 13ms

memory: 8856kb

input:

output:

561747634

result:

ok 1 number(s): "561747634"

Subtask #7:

score: 30

Accepted

Test #32:

score: 30

Accepted

time: 27ms

memory: 9104kb

input:

output:

602805814

result:

ok 1 number(s): "602805814"

Test #33:

score: 30

Accepted

time: 99ms

memory: 22488kb

input:

output:

898203793

result:

ok 1 number(s): "898203793"

Test #34:

score: 30

Accepted

time: 398ms

memory: 74176kb

input:

output:

101317224

result:

ok 1 number(s): "101317224"

Test #35:

score: 30

Accepted

time: 452ms

memory: 80596kb

input:

output:

114947085

result:

ok 1 number(s): "114947085"

Test #36:

score: 30

Accepted

time: 478ms

memory: 81908kb

input:

output:

460040939

result:

ok 1 number(s): "460040939"

Test #37:

score: 30

Accepted

time: 477ms

memory: 82036kb

input:

output:

780785591

result:

ok 1 number(s): "780785591"

Test #38:

score: 30

Accepted

time: 474ms

memory: 82076kb

input:

output:

742624725

result:

ok 1 number(s): "742624725"