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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
#72268#4812. Counting SequenceJinTianHaoML 2144ms924688kbC++171.7kb2023-01-15 11:45:222023-01-15 11:45:24

Judging History

你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2023-01-15 11:45:24]
  • 评测
  • 测评结果:ML
  • 用时:2144ms
  • 内存:924688kb
  • [2023-01-15 11:45:22]
  • 提交

answer

#include <bits/stdc++.h>
#define inf 1000000007
#define mod 998244353
// #define int long long
// #pragma GCC optimize("Ofast","inline","-ffast-math")
// #pragma GCC target("avx,sse2,sse3,sse4,mmx")
using namespace std;
template <typename T> void read(T &x){
	x=0;char ch=getchar();int fh=1;
	while (ch<'0'||ch>'9'){if (ch=='-')fh=-1;ch=getchar();}
	while (ch>='0'&&ch<='9')x=x*10+ch-'0',ch=getchar();
	x*=fh;
}
template <typename T> void write(T x) {
	if (x<0) x=-x,putchar('-');
	if (x>9) write(x/10);
	putchar(x%10+'0');
}
template <typename T> void writeln(T x) {
	write(x);
	puts("");
}
int n,c,siz,ans;
int dp1[2][600005];
int dp2[300005][1000];
signed main()
{
	// freopen(".in","r",stdin);
	// freopen(".out","w",stdout);
	read(n);read(c);
	siz=sqrt(2*n)-10;siz=max(siz,0);
	while((siz+2)*(siz+1)<=2*n) ++siz;
	dp1[1][n]=1;
	for(int i=1;i<siz;++i)
	{
		for(int j=0;j<=2*n;++j)
			dp1[i&1^1][j]=0;
		for(int j=0;j<=2*n;++j)
		{
			//add <
			if(j+i<=2*n) (dp1[i&1^1][j+i]+=dp1[i&1][j])%=mod;
			//add >
			if(j-i>=0) (dp1[i&1^1][j-i]+=1ll*c*dp1[i&1][j]%mod)%=mod;
		}
		for(int a=siz+1;a<=n;++a)
		{
			int sum=2*n-1ll*a*i;
			if(sum>=0&&sum<=2*n) (ans+=dp1[i&1][sum])%=mod;
		}
	}
	for(int i=1;i<=n;++i)
	{
		if(i<=siz) (dp2[i][i]+=1)%=mod;
		for(int j=1;j<1000;++j)
		{
			if(!dp2[i][j]) continue;
			if(i+j-1<=n&&j>1) (dp2[i+j-1][j-1]+=1ll*c*dp2[i][j]%mod)%=mod;
			if(i+j+1<=n&&j<999) (dp2[i+j+1][j+1]+=dp2[i][j])%=mod;
		}
	}
	for(int i=1;i<1000;++i)
		(ans+=dp2[n][i])%=mod;
	for(int a=siz+1;a<=n;++a)
		for(int m=siz;m<=siz;++m)
		{
			int sum=2*n-1ll*a*m;
			if(sum>=0&&sum<=2*n) (ans+=dp1[m&1][sum])%=mod;
		}
	writeln(ans);
	return 0;
}

详细

Test #1:

score: 100
Accepted
time: 0ms
memory: 7524kb

input:

5 3

output:

8

result:

ok 1 number(s): "8"

Test #2:

score: 0
Accepted
time: 2ms
memory: 5468kb

input:

1 0

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 4ms
memory: 15264kb

input:

2022 39

output:

273239559

result:

ok 1 number(s): "273239559"

Test #4:

score: 0
Accepted
time: 2ms
memory: 5380kb

input:

1 998244352

output:

1

result:

ok 1 number(s): "1"

Test #5:

score: 0
Accepted
time: 2ms
memory: 5384kb

input:

1 12345678

output:

1

result:

ok 1 number(s): "1"

Test #6:

score: 0
Accepted
time: 2ms
memory: 7552kb

input:

20 998998

output:

643731701

result:

ok 1 number(s): "643731701"

Test #7:

score: 0
Accepted
time: 3ms
memory: 7584kb

input:

23 123

output:

947753998

result:

ok 1 number(s): "947753998"

Test #8:

score: 0
Accepted
time: 3ms
memory: 7652kb

input:

50 5555

output:

745339864

result:

ok 1 number(s): "745339864"

Test #9:

score: 0
Accepted
time: 2ms
memory: 7896kb

input:

60 6666

output:

690992218

result:

ok 1 number(s): "690992218"

Test #10:

score: 0
Accepted
time: 3ms
memory: 7940kb

input:

100 50

output:

169678588

result:

ok 1 number(s): "169678588"

Test #11:

score: 0
Accepted
time: 1ms
memory: 9572kb

input:

500 88888

output:

216149701

result:

ok 1 number(s): "216149701"

Test #12:

score: 0
Accepted
time: 1ms
memory: 11276kb

input:

1000 213456

output:

270989457

result:

ok 1 number(s): "270989457"

Test #13:

score: 0
Accepted
time: 2ms
memory: 15180kb

input:

2000 119988

output:

756425375

result:

ok 1 number(s): "756425375"

Test #14:

score: 0
Accepted
time: 1ms
memory: 19172kb

input:

3000 998244352

output:

71841227

result:

ok 1 number(s): "71841227"

Test #15:

score: 0
Accepted
time: 5ms
memory: 19180kb

input:

3000 555555555

output:

79880116

result:

ok 1 number(s): "79880116"

Test #16:

score: 0
Accepted
time: 14ms
memory: 24496kb

input:

4321 1234

output:

949603993

result:

ok 1 number(s): "949603993"

Test #17:

score: 0
Accepted
time: 13ms
memory: 23884kb

input:

5000 0

output:

5

result:

ok 1 number(s): "5"

Test #18:

score: 0
Accepted
time: 8ms
memory: 29064kb

input:

5000 88888777

output:

833064960

result:

ok 1 number(s): "833064960"

Test #19:

score: 0
Accepted
time: 12ms
memory: 27152kb

input:

5000 35557777

output:

696388498

result:

ok 1 number(s): "696388498"

Test #20:

score: 0
Accepted
time: 41ms
memory: 46556kb

input:

10000 123456

output:

434296902

result:

ok 1 number(s): "434296902"

Test #21:

score: 0
Accepted
time: 75ms
memory: 85620kb

input:

20000 555555

output:

34806915

result:

ok 1 number(s): "34806915"

Test #22:

score: 0
Accepted
time: 118ms
memory: 126728kb

input:

30000 777888999

output:

58443551

result:

ok 1 number(s): "58443551"

Test #23:

score: 0
Accepted
time: 364ms
memory: 202824kb

input:

50000 2

output:

90102905

result:

ok 1 number(s): "90102905"

Test #24:

score: 0
Accepted
time: 439ms
memory: 280944kb

input:

70000 77998866

output:

202638568

result:

ok 1 number(s): "202638568"

Test #25:

score: 0
Accepted
time: 706ms
memory: 398176kb

input:

100000 998244352

output:

360520717

result:

ok 1 number(s): "360520717"

Test #26:

score: 0
Accepted
time: 725ms
memory: 398048kb

input:

100000 555555555

output:

613886009

result:

ok 1 number(s): "613886009"

Test #27:

score: 0
Accepted
time: 1241ms
memory: 593308kb

input:

150000 233333

output:

381065878

result:

ok 1 number(s): "381065878"

Test #28:

score: 0
Accepted
time: 1335ms
memory: 593372kb

input:

150000 20050117

output:

269891864

result:

ok 1 number(s): "269891864"

Test #29:

score: 0
Accepted
time: 2009ms
memory: 789464kb

input:

200000 114514

output:

262861613

result:

ok 1 number(s): "262861613"

Test #30:

score: 0
Accepted
time: 2006ms
memory: 788740kb

input:

200000 1919810

output:

77872388

result:

ok 1 number(s): "77872388"

Test #31:

score: 0
Accepted
time: 2144ms
memory: 924688kb

input:

300000 0

output:

12

result:

ok 1 number(s): "12"

Test #32:

score: -100
Memory Limit Exceeded

input:

300000 1

output:


result: