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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
#398369	#5406. 随机游走	le0n	100 ✓	639ms	82076kb	C++14	825b	2024-04-25 11:13:19	2024-04-25 11:13:20

Judging History

你现在查看的是最新测评结果

[2024-04-25 11:13:20]
评测

测评结果：100
用时：639ms
内存：82076kb

查看

[2024-04-25 11:13:19]
提交

answer

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

const int mod = 1e9 + 7;
int fac[10000005], inv[10000005];
int qpow(int x, int y)
{
	int ans = 1;
	while(y)
	{
		if(y & 1)
			ans = (ll)ans * x % mod;
		x = (ll)x * x % mod;
		y >>= 1;
	}
	return ans;
}

int main()
{
	int n, i, r, ans = 0, tmp;
	scanf("%d", &n);
	fac[0] = 1;
	for(i = 1; i <= 2 * n; i++)
		fac[i] = (ll)fac[i - 1] * i % mod;
	inv[2 * n] = qpow(fac[2 * n], mod - 2);
	for(i = 2 * n; i >= 1; i--)
		inv[i - 1] = (ll)inv[i] * i % mod;
	r = qpow(2 * n + 1, mod - 2);
	for(i = 0; i <= n; i++)
	{
		tmp = (ll)inv[i] * inv[2 * n - i] % mod * r % mod * qpow(n - i, 2 * n + 1) % mod;
		if(i & 1)
			tmp = mod - tmp;
		ans = (ans + tmp) % mod;
	}
	ans = (ll)ans * 2 % mod;
	printf("%d\n", ans);
	return 0;
}

源文件, 语言: C++14

詳細信息

Subtask #1:

score: 5

Accepted

Test #1:

score: 5

Accepted

time: 1ms

memory: 3916kb

input:

output:

333333336

result:

ok 1 number(s): "333333336"

Test #2:

score: 5

Accepted

time: 1ms

memory: 3916kb

input:

output:

266666669

result:

ok 1 number(s): "266666669"

Test #3:

score: 5

Accepted

time: 1ms

memory: 3776kb

input:

output:

769047625

result:

ok 1 number(s): "769047625"

Subtask #2:

score: 10

Accepted

Test #4:

score: 10

Accepted

time: 0ms

memory: 3768kb

input:

output:

877865968

result:

ok 1 number(s): "877865968"

Test #5:

score: 10

Accepted

time: 0ms

memory: 3776kb

input:

output:

733342859

result:

ok 1 number(s): "733342859"

Test #6:

score: 10

Accepted

time: 0ms

memory: 3960kb

input:

output:

655899114

result:

ok 1 number(s): "655899114"

Test #7:

score: 10

Accepted

time: 1ms

memory: 3892kb

input:

output:

946326757

result:

ok 1 number(s): "946326757"

Test #8:

score: 10

Accepted

time: 0ms

memory: 3828kb

input:

output:

230714822

result:

ok 1 number(s): "230714822"

Test #9:

score: 10

Accepted

time: 0ms

memory: 3768kb

input:

output:

782967541

result:

ok 1 number(s): "782967541"

Test #10:

score: 10

Accepted

time: 0ms

memory: 3912kb

input:

output:

732371611

result:

ok 1 number(s): "732371611"

Subtask #3:

score: 10

Accepted

Test #11:

score: 10

Accepted

time: 0ms

memory: 3776kb

input:

output:

677123472

result:

ok 1 number(s): "677123472"

Test #12:

score: 10

Accepted

time: 1ms

memory: 3828kb

input:

output:

168974634

result:

ok 1 number(s): "168974634"

Test #13:

score: 10

Accepted

time: 0ms

memory: 3912kb

input:

output:

213343876

result:

ok 1 number(s): "213343876"

Test #14:

score: 10

Accepted

time: 0ms

memory: 3952kb

input:

output:

631124616

result:

ok 1 number(s): "631124616"

Subtask #4:

score: 15

Accepted

Test #15:

score: 15

Accepted

time: 0ms

memory: 3892kb

input:

output:

349256161

result:

ok 1 number(s): "349256161"

Test #16:

score: 15

Accepted

time: 0ms

memory: 3832kb

input:

output:

351095881

result:

ok 1 number(s): "351095881"

Test #17:

score: 15

Accepted

time: 0ms

memory: 3904kb

input:

output:

895504391

result:

ok 1 number(s): "895504391"

Test #18:

score: 15

Accepted

time: 0ms

memory: 3920kb

input:

output:

923555376

result:

ok 1 number(s): "923555376"

Test #19:

score: 15

Accepted

time: 0ms

memory: 3968kb

input:

output:

512220517

result:

ok 1 number(s): "512220517"

Subtask #5:

score: 15

Accepted

Test #20:

score: 15

Accepted

time: 0ms

memory: 3924kb

input:

output:

255062346

result:

ok 1 number(s): "255062346"

Test #21:

score: 15

Accepted

time: 1ms

memory: 3920kb

input:

output:

735041605

result:

ok 1 number(s): "735041605"

Test #22:

score: 15

Accepted

time: 1ms

memory: 3944kb

input:

output:

208261384

result:

ok 1 number(s): "208261384"

Test #23:

score: 15

Accepted

time: 1ms

memory: 3908kb

input:

output:

875427987

result:

ok 1 number(s): "875427987"

Test #24:

score: 15

Accepted

time: 1ms

memory: 3940kb

input:

output:

571776252

result:

ok 1 number(s): "571776252"

Test #25:

score: 15

Accepted

time: 0ms

memory: 3984kb

input:

output:

12983695

result:

ok 1 number(s): "12983695"

Subtask #6:

score: 15

Accepted

Test #26:

score: 15

Accepted

time: 1ms

memory: 3956kb

input:

output:

977435333

result:

ok 1 number(s): "977435333"

Test #27:

score: 15

Accepted

time: 7ms

memory: 4800kb

input:

output:

312666196

result:

ok 1 number(s): "312666196"

Test #28:

score: 15

Accepted

time: 15ms

memory: 6472kb

input:

output:

163767254

result:

ok 1 number(s): "163767254"

Test #29:

score: 15

Accepted

time: 22ms

memory: 7060kb

input:

output:

911833524

result:

ok 1 number(s): "911833524"

Test #30:

score: 15

Accepted

time: 22ms

memory: 7008kb

input:

output:

910277128

result:

ok 1 number(s): "910277128"

Test #31:

score: 15

Accepted

time: 23ms

memory: 7072kb

input:

output:

561747634

result:

ok 1 number(s): "561747634"

Subtask #7:

score: 30

Accepted

Test #32:

score: 30

Accepted

time: 36ms

memory: 8748kb

input:

output:

602805814

result:

ok 1 number(s): "602805814"

Test #33:

score: 30

Accepted

time: 134ms

memory: 21624kb

input:

output:

898203793

result:

ok 1 number(s): "898203793"

Test #34:

score: 30

Accepted

time: 536ms

memory: 73080kb

input:

output:

101317224

result:

ok 1 number(s): "101317224"

Test #35:

score: 30

Accepted

time: 611ms

memory: 80448kb

input:

output:

114947085

result:

ok 1 number(s): "114947085"

Test #36:

score: 30

Accepted

time: 633ms

memory: 81996kb

input:

output:

460040939

result:

ok 1 number(s): "460040939"

Test #37:

score: 30

Accepted

time: 636ms

memory: 82076kb

input:

output:

780785591

result:

ok 1 number(s): "780785591"

Test #38:

score: 30

Accepted

time: 639ms

memory: 82040kb

input:

output:

742624725

result:

ok 1 number(s): "742624725"