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ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#661795 | #6417. Classical Summation Problem | ucup-team5271# | AC ✓ | 356ms | 11552kb | C++17 | 713b | 2024-10-20 18:12:23 | 2024-10-20 18:12:23 |
Judging History
answer
#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=1e6,p=998244353,I2=p+1>>1;
static int f[N+1];
inline void chadd(int &x,int y){
if((x+=y)>=p)x-=p;
}
inline int qpow(int a,int b){
int r=1;
while(b){
if(b&1)(r*=a)%=p;
(a*=a)%=p,b>>=1;
}
return r;
}
inline int com(int n,int m){
return f[n]*qpow(f[m]*f[n-m]%p,p-2)%p;
}
main(){
ios::sync_with_stdio(false);
for(int i=f[0]=1;i<=N;i++)
f[i]=f[i-1]*i%p;
int n,k,c=0; cin>>n>>k;
if(k&1)cout<<(n+1)*I2%p*qpow(n,k)%p<<endl,exit(0);
for(int i=1;i<n;i++)
chadd(c,qpow(i*(n-i)%p,k>>1)*com(k,k>>1)%p*qpow(qpow(n,k),p-2)%p);
cout<<(n+1-c+p)*I2%p*qpow(n,k)%p<<endl;
return 0;
}
Details
Tip: Click on the bar to expand more detailed information
Test #1:
score: 100
Accepted
time: 0ms
memory: 11484kb
input:
3 2
output:
14
result:
ok 1 number(s): "14"
Test #2:
score: 0
Accepted
time: 6ms
memory: 11452kb
input:
5 3
output:
375
result:
ok 1 number(s): "375"
Test #3:
score: 0
Accepted
time: 5ms
memory: 11540kb
input:
2 2
output:
5
result:
ok 1 number(s): "5"
Test #4:
score: 0
Accepted
time: 3ms
memory: 11424kb
input:
10 9
output:
508778235
result:
ok 1 number(s): "508778235"
Test #5:
score: 0
Accepted
time: 6ms
memory: 11416kb
input:
69 3
output:
11497815
result:
ok 1 number(s): "11497815"
Test #6:
score: 0
Accepted
time: 0ms
memory: 11464kb
input:
994 515
output:
33689623
result:
ok 1 number(s): "33689623"
Test #7:
score: 0
Accepted
time: 3ms
memory: 11492kb
input:
4476 6182
output:
114894183
result:
ok 1 number(s): "114894183"
Test #8:
score: 0
Accepted
time: 3ms
memory: 11424kb
input:
58957 12755
output:
932388891
result:
ok 1 number(s): "932388891"
Test #9:
score: 0
Accepted
time: 70ms
memory: 11416kb
input:
218138 28238
output:
392861201
result:
ok 1 number(s): "392861201"
Test #10:
score: 0
Accepted
time: 222ms
memory: 11472kb
input:
644125 316810
output:
420621854
result:
ok 1 number(s): "420621854"
Test #11:
score: 0
Accepted
time: 216ms
memory: 11420kb
input:
612914 505428
output:
973686286
result:
ok 1 number(s): "973686286"
Test #12:
score: 0
Accepted
time: 6ms
memory: 11536kb
input:
998216 938963
output:
251335926
result:
ok 1 number(s): "251335926"
Test #13:
score: 0
Accepted
time: 5ms
memory: 11424kb
input:
990516 996933
output:
549551960
result:
ok 1 number(s): "549551960"
Test #14:
score: 0
Accepted
time: 355ms
memory: 11540kb
input:
999019 999012
output:
637189128
result:
ok 1 number(s): "637189128"
Test #15:
score: 0
Accepted
time: 354ms
memory: 11424kb
input:
999928 999950
output:
185229465
result:
ok 1 number(s): "185229465"
Test #16:
score: 0
Accepted
time: 6ms
memory: 11416kb
input:
999999 999999
output:
384164916
result:
ok 1 number(s): "384164916"
Test #17:
score: 0
Accepted
time: 346ms
memory: 11476kb
input:
999999 1000000
output:
696165930
result:
ok 1 number(s): "696165930"
Test #18:
score: 0
Accepted
time: 6ms
memory: 11536kb
input:
1000000 999999
output:
219071706
result:
ok 1 number(s): "219071706"
Test #19:
score: 0
Accepted
time: 349ms
memory: 11472kb
input:
1000000 1000000
output:
128206597
result:
ok 1 number(s): "128206597"
Test #20:
score: 0
Accepted
time: 6ms
memory: 11468kb
input:
2 10
output:
1410
result:
ok 1 number(s): "1410"
Test #21:
score: 0
Accepted
time: 6ms
memory: 11420kb
input:
84 16
output:
297627153
result:
ok 1 number(s): "297627153"
Test #22:
score: 0
Accepted
time: 3ms
memory: 11492kb
input:
643 800
output:
489237163
result:
ok 1 number(s): "489237163"
Test #23:
score: 0
Accepted
time: 8ms
memory: 11484kb
input:
9903 880
output:
595167333
result:
ok 1 number(s): "595167333"
Test #24:
score: 0
Accepted
time: 37ms
memory: 11500kb
input:
97446 89750
output:
410205549
result:
ok 1 number(s): "410205549"
Test #25:
score: 0
Accepted
time: 70ms
memory: 11552kb
input:
186460 646474
output:
32638530
result:
ok 1 number(s): "32638530"
Test #26:
score: 0
Accepted
time: 173ms
memory: 11536kb
input:
508940 244684
output:
598321755
result:
ok 1 number(s): "598321755"
Test #27:
score: 0
Accepted
time: 204ms
memory: 11420kb
input:
583646 557758
output:
858695621
result:
ok 1 number(s): "858695621"
Test #28:
score: 0
Accepted
time: 337ms
memory: 11536kb
input:
969610 992608
output:
256683498
result:
ok 1 number(s): "256683498"
Test #29:
score: 0
Accepted
time: 343ms
memory: 11468kb
input:
995106 996434
output:
411791999
result:
ok 1 number(s): "411791999"
Test #30:
score: 0
Accepted
time: 351ms
memory: 11496kb
input:
999961 999872
output:
61222370
result:
ok 1 number(s): "61222370"
Test #31:
score: 0
Accepted
time: 355ms
memory: 11416kb
input:
999977 999908
output:
831096762
result:
ok 1 number(s): "831096762"
Test #32:
score: 0
Accepted
time: 356ms
memory: 11484kb
input:
999992 999998
output:
562977678
result:
ok 1 number(s): "562977678"
Test #33:
score: 0
Accepted
time: 222ms
memory: 11492kb
input:
1000000 2
output:
118436113
result:
ok 1 number(s): "118436113"
Test #34:
score: 0
Accepted
time: 6ms
memory: 11496kb
input:
2 1000000
output:
298823641
result:
ok 1 number(s): "298823641"