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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 |
---|---|---|---|---|---|---|---|---|---|
#197514 | #6417. Classical Summation Problem | ucup-team870# | AC ✓ | 46ms | 19304kb | C++14 | 1.0kb | 2023-10-02 16:39:46 | 2023-10-02 16:39:46 |
Judging History
answer
#include <bits/stdc++.h>
#define rep(i,l,r) for(int i=l; i<=r; i++)
#define per(i,r,l) for(int i=r; i>=l; i--)
#define IOS {cin.tie(0);cout.tie(0);ios::sync_with_stdio(0);}
using namespace std;
typedef long long ll;
const int N=1e6+6,mod=998244353;
void add(ll &x,ll y){x=(x+y)%mod;}
ll qp(ll x,ll y){
ll res=1;
while(y){
if(y&1)res=res*x%mod;
x=x*x%mod; y>>=1;
}
return res;
}
ll fac[N],inv[N];
ll C(int i,int j){
return fac[i]*inv[j]%mod*inv[i-j]%mod;
}
int main() {
const int M=1e6;
fac[0]=1; rep(i,1,M)fac[i]=fac[i-1]*i%mod;
inv[M]=qp(fac[M],mod-2); per(i,M,1)inv[i-1]=inv[i]*i%mod;
int n,k;cin>>n>>k;
ll ans=0,nk=qp(n,k);
rep(i,1,n/2){
if(i*2==n)break;
if(k&1){
add(ans,nk);
}
else{
add(ans,nk+C(k,k/2)*qp(1ll*i*(n-i)%mod,k/2) );
}
}
if(n%2==0){
int x=n/2; ll v=qp(x,k);
rep(i,(k+1)/2,k)add(ans,C(k,i)*v%mod);
}
cout<<(n*nk-ans+mod)%mod;
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 11ms
memory: 19148kb
input:
3 2
output:
14
result:
ok 1 number(s): "14"
Test #2:
score: 0
Accepted
time: 6ms
memory: 19300kb
input:
5 3
output:
375
result:
ok 1 number(s): "375"
Test #3:
score: 0
Accepted
time: 9ms
memory: 19112kb
input:
2 2
output:
5
result:
ok 1 number(s): "5"
Test #4:
score: 0
Accepted
time: 10ms
memory: 19148kb
input:
10 9
output:
508778235
result:
ok 1 number(s): "508778235"
Test #5:
score: 0
Accepted
time: 6ms
memory: 19144kb
input:
69 3
output:
11497815
result:
ok 1 number(s): "11497815"
Test #6:
score: 0
Accepted
time: 7ms
memory: 19220kb
input:
994 515
output:
33689623
result:
ok 1 number(s): "33689623"
Test #7:
score: 0
Accepted
time: 7ms
memory: 19284kb
input:
4476 6182
output:
114894183
result:
ok 1 number(s): "114894183"
Test #8:
score: 0
Accepted
time: 11ms
memory: 19296kb
input:
58957 12755
output:
932388891
result:
ok 1 number(s): "932388891"
Test #9:
score: 0
Accepted
time: 11ms
memory: 19236kb
input:
218138 28238
output:
392861201
result:
ok 1 number(s): "392861201"
Test #10:
score: 0
Accepted
time: 25ms
memory: 19208kb
input:
644125 316810
output:
420621854
result:
ok 1 number(s): "420621854"
Test #11:
score: 0
Accepted
time: 30ms
memory: 19204kb
input:
612914 505428
output:
973686286
result:
ok 1 number(s): "973686286"
Test #12:
score: 0
Accepted
time: 10ms
memory: 19232kb
input:
998216 938963
output:
251335926
result:
ok 1 number(s): "251335926"
Test #13:
score: 0
Accepted
time: 3ms
memory: 19220kb
input:
990516 996933
output:
549551960
result:
ok 1 number(s): "549551960"
Test #14:
score: 0
Accepted
time: 44ms
memory: 19228kb
input:
999019 999012
output:
637189128
result:
ok 1 number(s): "637189128"
Test #15:
score: 0
Accepted
time: 41ms
memory: 19108kb
input:
999928 999950
output:
185229465
result:
ok 1 number(s): "185229465"
Test #16:
score: 0
Accepted
time: 9ms
memory: 19232kb
input:
999999 999999
output:
384164916
result:
ok 1 number(s): "384164916"
Test #17:
score: 0
Accepted
time: 39ms
memory: 19276kb
input:
999999 1000000
output:
696165930
result:
ok 1 number(s): "696165930"
Test #18:
score: 0
Accepted
time: 14ms
memory: 19280kb
input:
1000000 999999
output:
219071706
result:
ok 1 number(s): "219071706"
Test #19:
score: 0
Accepted
time: 44ms
memory: 19168kb
input:
1000000 1000000
output:
128206597
result:
ok 1 number(s): "128206597"
Test #20:
score: 0
Accepted
time: 11ms
memory: 19108kb
input:
2 10
output:
1410
result:
ok 1 number(s): "1410"
Test #21:
score: 0
Accepted
time: 5ms
memory: 19244kb
input:
84 16
output:
297627153
result:
ok 1 number(s): "297627153"
Test #22:
score: 0
Accepted
time: 10ms
memory: 19280kb
input:
643 800
output:
489237163
result:
ok 1 number(s): "489237163"
Test #23:
score: 0
Accepted
time: 7ms
memory: 19152kb
input:
9903 880
output:
595167333
result:
ok 1 number(s): "595167333"
Test #24:
score: 0
Accepted
time: 6ms
memory: 19220kb
input:
97446 89750
output:
410205549
result:
ok 1 number(s): "410205549"
Test #25:
score: 0
Accepted
time: 17ms
memory: 19148kb
input:
186460 646474
output:
32638530
result:
ok 1 number(s): "32638530"
Test #26:
score: 0
Accepted
time: 21ms
memory: 19304kb
input:
508940 244684
output:
598321755
result:
ok 1 number(s): "598321755"
Test #27:
score: 0
Accepted
time: 20ms
memory: 19296kb
input:
583646 557758
output:
858695621
result:
ok 1 number(s): "858695621"
Test #28:
score: 0
Accepted
time: 41ms
memory: 19284kb
input:
969610 992608
output:
256683498
result:
ok 1 number(s): "256683498"
Test #29:
score: 0
Accepted
time: 46ms
memory: 19244kb
input:
995106 996434
output:
411791999
result:
ok 1 number(s): "411791999"
Test #30:
score: 0
Accepted
time: 42ms
memory: 19280kb
input:
999961 999872
output:
61222370
result:
ok 1 number(s): "61222370"
Test #31:
score: 0
Accepted
time: 40ms
memory: 19220kb
input:
999977 999908
output:
831096762
result:
ok 1 number(s): "831096762"
Test #32:
score: 0
Accepted
time: 42ms
memory: 19112kb
input:
999992 999998
output:
562977678
result:
ok 1 number(s): "562977678"
Test #33:
score: 0
Accepted
time: 10ms
memory: 19236kb
input:
1000000 2
output:
118436113
result:
ok 1 number(s): "118436113"
Test #34:
score: 0
Accepted
time: 13ms
memory: 19304kb
input:
2 1000000
output:
298823641
result:
ok 1 number(s): "298823641"