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QOJ
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 |
---|---|---|---|---|---|---|---|---|---|
#65863 | #4843. Infectious Disease | myee | AC ✓ | 912ms | 332532kb | C++14 | 1.9kb | 2022-12-03 21:53:03 | 2022-12-03 21:53:07 |
Judging History
answer
#ifdef MYEE
#pragma GCC optimize("-O2")
#endif
#include <bits/stdc++.h>
using uint = unsigned;
using ullt = unsigned long long;
const ullt Mod=1e9+7;
struct modint{
ullt v;
modint():v(0){}
modint(ullt v):v(v%Mod){}
ullt&operator()(){return v;}
friend modint operator+(modint a,modint b){return a()+b();}
friend modint operator-(modint a,modint b){return a()+Mod-b();}
friend modint operator*(modint a,modint b){return a()*b();}
friend modint operator^(modint a,ullt b){
modint ans(1);
while(b){
if(b&1)ans*=a;
a*=a,b>>=1;
}
return ans;
}
modint inv(){return*this^(Mod-2);}
modint operator+=(modint b){return*this=*this+b;}
modint operator-=(modint b){return*this=*this-b;}
modint operator*=(modint b){return*this=*this*b;}
void println(){printf("%llu\n",v);}
};
modint P[20000005],Q[20000005];
modint Dp[1u<<20|1],Last[1u<<20|1];
int main(){
#ifdef MYEE
freopen("QAQ.in","r",stdin);
#endif
P[0]=1;for(uint i=1;i<=20000000;i++)P[i]=P[i-1]*i;
Q[20000000]=P[20000000].inv();for(uint i=20000000;i;i--)Q[i-1]=Q[i]*i;
uint n;scanf("%u",&n);
Dp[1]=1;uint cnt2=1,cnt3=1;
modint ans;
for(uint k=1;cnt3<=n;k++){
if(cnt3*3>=n){
for(uint i=1;i<=cnt2;i++)ans+=Dp[i]*k;
break;
}
uint A=n-cnt3,B=2*cnt3;
for(uint i=1;i<=cnt2*2;i++)Last[i]=0;
for(uint i=1;i<=cnt2;i++)
Last[std::min(n-cnt3,i*2)]+=Dp[i],Dp[i]=0;
cnt2*=2;
for(uint m=1;m<=cnt2;m++){
modint v=Last[m]*P[m]*P[A-m];
for(uint t=std::min(m,B);~t&&A+t>=B+m;t--)
Dp[m-t]+=v*Q[t]*Q[B-t];
}
for(uint m=0;m<=cnt2&&m+B<=A;m++)
Dp[m]*=Q[A]*P[B]*P[A-B]*Q[m]*Q[A-B-m];
ans+=Dp[0]*k,Dp[0]=0;
cnt3*=3;
}
ans.println();
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 285ms
memory: 332340kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 218ms
memory: 332352kb
input:
114
output:
505208013
result:
ok 1 number(s): "505208013"
Test #3:
score: 0
Accepted
time: 894ms
memory: 332352kb
input:
14000000
output:
44565093
result:
ok 1 number(s): "44565093"
Test #4:
score: 0
Accepted
time: 894ms
memory: 332344kb
input:
12345678
output:
123143093
result:
ok 1 number(s): "123143093"
Test #5:
score: 0
Accepted
time: 295ms
memory: 332500kb
input:
776777
output:
764022068
result:
ok 1 number(s): "764022068"
Test #6:
score: 0
Accepted
time: 217ms
memory: 332424kb
input:
3
output:
1
result:
ok 1 number(s): "1"
Test #7:
score: 0
Accepted
time: 264ms
memory: 332352kb
input:
4
output:
666666673
result:
ok 1 number(s): "666666673"
Test #8:
score: 0
Accepted
time: 246ms
memory: 332372kb
input:
5
output:
833333341
result:
ok 1 number(s): "833333341"
Test #9:
score: 0
Accepted
time: 251ms
memory: 332396kb
input:
6
output:
300000004
result:
ok 1 number(s): "300000004"
Test #10:
score: 0
Accepted
time: 233ms
memory: 332340kb
input:
7
output:
533333339
result:
ok 1 number(s): "533333339"
Test #11:
score: 0
Accepted
time: 254ms
memory: 332508kb
input:
8
output:
952380961
result:
ok 1 number(s): "952380961"
Test #12:
score: 0
Accepted
time: 246ms
memory: 332364kb
input:
9
output:
964285723
result:
ok 1 number(s): "964285723"
Test #13:
score: 0
Accepted
time: 246ms
memory: 332356kb
input:
10
output:
416666672
result:
ok 1 number(s): "416666672"
Test #14:
score: 0
Accepted
time: 272ms
memory: 332396kb
input:
26
output:
990086590
result:
ok 1 number(s): "990086590"
Test #15:
score: 0
Accepted
time: 238ms
memory: 332364kb
input:
27
output:
528360342
result:
ok 1 number(s): "528360342"
Test #16:
score: 0
Accepted
time: 249ms
memory: 332344kb
input:
28
output:
273239648
result:
ok 1 number(s): "273239648"
Test #17:
score: 0
Accepted
time: 402ms
memory: 332344kb
input:
4782967
output:
332194401
result:
ok 1 number(s): "332194401"
Test #18:
score: 0
Accepted
time: 419ms
memory: 332504kb
input:
4782968
output:
362625027
result:
ok 1 number(s): "362625027"
Test #19:
score: 0
Accepted
time: 433ms
memory: 332364kb
input:
4782969
output:
971032452
result:
ok 1 number(s): "971032452"
Test #20:
score: 0
Accepted
time: 435ms
memory: 332420kb
input:
4782970
output:
452836984
result:
ok 1 number(s): "452836984"
Test #21:
score: 0
Accepted
time: 387ms
memory: 332532kb
input:
4782971
output:
349324970
result:
ok 1 number(s): "349324970"
Test #22:
score: 0
Accepted
time: 404ms
memory: 332424kb
input:
4782972
output:
46862963
result:
ok 1 number(s): "46862963"
Test #23:
score: 0
Accepted
time: 240ms
memory: 332508kb
input:
114514
output:
972669965
result:
ok 1 number(s): "972669965"
Test #24:
score: 0
Accepted
time: 401ms
memory: 332344kb
input:
1919810
output:
482430785
result:
ok 1 number(s): "482430785"
Test #25:
score: 0
Accepted
time: 912ms
memory: 332376kb
input:
8877877
output:
486769120
result:
ok 1 number(s): "486769120"