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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#320594 | #8211. Enumerating Substrings | ucup-team197# | AC ✓ | 19ms | 34204kb | C++14 | 1.2kb | 2024-02-03 18:28:26 | 2024-02-03 18:28:26 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll mod=1e9+7;
ll n,m,k;
ll p[1000001];
ll ways[2005];
ll dp[2005][2005];
ll C[2005];
ll pw(ll x,ll y){
if(y==0) return 1;
if(y%2) return x*pw(x,y-1)%mod;
ll res=pw(x,y/2);
return res*res%mod;
}
int main(){
ios::sync_with_stdio(false);cin.tie(0);
cin >> n >> m >> k;
p[0]=1;
for(int i=1; i<=n ;i++) p[i]=p[i-1]*k%mod;
C[0]=1;
for(int i=1; i<=m ;i++) C[i]=C[i-1]*(k-i+1)%mod;
dp[0][0]=1;
for(int i=1; i<=m ;i++){
for(int j=i%2; j<=i ;j+=2){
if(j!=i) dp[i][j]+=(j+1)*dp[i-1][j+1];
if(j!=0) dp[i][j]+=dp[i-1][j-1];
dp[i][j]%=mod;
//cout << i << ' ' << j << ' ' << dp[i][j] << endl;
}
}
ll ans=0;
for(int i=0; i*2<=m ;i++){
for(int r=m%2; r<=m-2*i ;r+=2){
ways[i]+=dp[m-2*i][r]*C[(m+r)/2];
ways[i]%=mod;
}
}
for(int i=1; i<=m ;i++) ways[0]=(ways[0]+mod-ways[i])%mod;
for(int i=0; i*2<=m ;i++){
ll res=0;
for(int j=1,len=m; len<=n ;j++,len+=m-i){
if(j>1 && i==0) continue;
ll cur=p[n-len]*(n-len+1)%mod;
//cout << "! " << i <<' ' << j << ' ' << cur << endl;
if(j%2) res=(res+cur)%mod;
else res=(res+mod-cur)%mod;
}
ans=(ans+res*ways[i])%mod;
}
cout << ans << '\n';
}
这程序好像有点Bug,我给组数据试试?
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 0ms
memory: 5748kb
input:
4 2 3
output:
228
result:
ok 1 number(s): "228"
Test #2:
score: 0
Accepted
time: 19ms
memory: 34204kb
input:
999999 1999 12345678
output:
52352722
result:
ok 1 number(s): "52352722"
Test #3:
score: 0
Accepted
time: 0ms
memory: 5796kb
input:
7 4 2
output:
182
result:
ok 1 number(s): "182"
Test #4:
score: 0
Accepted
time: 1ms
memory: 5792kb
input:
4 3 4
output:
480
result:
ok 1 number(s): "480"
Test #5:
score: 0
Accepted
time: 1ms
memory: 5784kb
input:
3 1 1
output:
3
result:
ok 1 number(s): "3"
Test #6:
score: 0
Accepted
time: 1ms
memory: 5760kb
input:
5 5 1
output:
0
result:
ok 1 number(s): "0"
Test #7:
score: 0
Accepted
time: 0ms
memory: 5688kb
input:
7 4 3
output:
5784
result:
ok 1 number(s): "5784"
Test #8:
score: 0
Accepted
time: 1ms
memory: 5672kb
input:
5 2 4
output:
3932
result:
ok 1 number(s): "3932"
Test #9:
score: 0
Accepted
time: 1ms
memory: 5676kb
input:
8 2 2
output:
1522
result:
ok 1 number(s): "1522"
Test #10:
score: 0
Accepted
time: 1ms
memory: 5668kb
input:
8 1 2
output:
2048
result:
ok 1 number(s): "2048"
Test #11:
score: 0
Accepted
time: 1ms
memory: 5768kb
input:
7 5 3
output:
2430
result:
ok 1 number(s): "2430"
Test #12:
score: 0
Accepted
time: 1ms
memory: 5680kb
input:
10 4 3
output:
272004
result:
ok 1 number(s): "272004"
Test #13:
score: 0
Accepted
time: 8ms
memory: 15736kb
input:
675978 614 2
output:
0
result:
ok 1 number(s): "0"
Test #14:
score: 0
Accepted
time: 3ms
memory: 8000kb
input:
244613 38 1
output:
0
result:
ok 1 number(s): "0"
Test #15:
score: 0
Accepted
time: 8ms
memory: 21868kb
input:
186293 1462 1
output:
0
result:
ok 1 number(s): "0"
Test #16:
score: 0
Accepted
time: 6ms
memory: 12392kb
input:
24867 886 1
output:
0
result:
ok 1 number(s): "0"
Test #17:
score: 0
Accepted
time: 12ms
memory: 20376kb
input:
976164 1014 2
output:
0
result:
ok 1 number(s): "0"
Test #18:
score: 0
Accepted
time: 3ms
memory: 7800kb
input:
179356 2 716844809
output:
577866092
result:
ok 1 number(s): "577866092"
Test #19:
score: 0
Accepted
time: 4ms
memory: 10388kb
input:
621001 130 310625363
output:
892869197
result:
ok 1 number(s): "892869197"
Test #20:
score: 0
Accepted
time: 13ms
memory: 16108kb
input:
678862 850 754662812
output:
582264789
result:
ok 1 number(s): "582264789"
Test #21:
score: 0
Accepted
time: 11ms
memory: 19460kb
input:
650845 978 348443366
output:
825425732
result:
ok 1 number(s): "825425732"
Test #22:
score: 0
Accepted
time: 6ms
memory: 13464kb
input:
669914 402 87448112
output:
318098088
result:
ok 1 number(s): "318098088"
Test #23:
score: 0
Accepted
time: 7ms
memory: 15320kb
input:
998593 530 681228665
output:
408255654
result:
ok 1 number(s): "408255654"
Test #24:
score: 0
Accepted
time: 4ms
memory: 30588kb
input:
369361 1954 125266115
output:
509912384
result:
ok 1 number(s): "509912384"
Test #25:
score: 0
Accepted
time: 13ms
memory: 25048kb
input:
900226 1378 424079373
output:
406320917
result:
ok 1 number(s): "406320917"
Test #26:
score: 0
Accepted
time: 7ms
memory: 22676kb
input:
334887 1506 17859926
output:
503264679
result:
ok 1 number(s): "503264679"
Test #27:
score: 0
Accepted
time: 11ms
memory: 14416kb
input:
936048 544 53978328
output:
548647866
result:
ok 1 number(s): "548647866"
Test #28:
score: 0
Accepted
time: 7ms
memory: 19132kb
input:
152789 1264 792983073
output:
839541707
result:
ok 1 number(s): "839541707"
Test #29:
score: 0
Accepted
time: 3ms
memory: 25032kb
input:
714493 1392 91796331
output:
721071046
result:
ok 1 number(s): "721071046"
Test #30:
score: 0
Accepted
time: 4ms
memory: 13728kb
input:
269571 816 830801077
output:
330064211
result:
ok 1 number(s): "330064211"
Test #31:
score: 0
Accepted
time: 12ms
memory: 19076kb
input:
845120 944 424581630
output:
348960190
result:
ok 1 number(s): "348960190"
Test #32:
score: 0
Accepted
time: 8ms
memory: 11816kb
input:
533990 368 163586376
output:
522092095
result:
ok 1 number(s): "522092095"
Test #33:
score: 0
Accepted
time: 8ms
memory: 25096kb
input:
181707 1792 462399634
output:
373795106
result:
ok 1 number(s): "373795106"
Test #34:
score: 0
Accepted
time: 8ms
memory: 31212kb
input:
417349 1920 761212891
output:
587051329
result:
ok 1 number(s): "587051329"
Test #35:
score: 0
Accepted
time: 8ms
memory: 22272kb
input:
526583 1344 500217637
output:
108767800
result:
ok 1 number(s): "108767800"
Test #36:
score: 0
Accepted
time: 7ms
memory: 17316kb
input:
867054 769 93998191
output:
239123369
result:
ok 1 number(s): "239123369"
Extra Test:
score: 0
Extra Test Passed