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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 |
---|---|---|---|---|---|---|---|---|---|
#189074 | #6736. Alice and Bob | zwp1234 | AC ✓ | 106ms | 159856kb | C++17 | 2.5kb | 2023-09-26 20:29:23 | 2023-09-26 20:29:24 |
Judging History
answer
//# pragma GCC optimize(2)
#include <bits/stdc++.h>
#define int long long
#define SZ(x) (int)(x).size()
#define fs first
#define sc second
#define PII pair<int,int>
#define ls(u) (u)<<1
#define rs(u) (u)<<1|1
#define pb push_back
#define eb emplace_back
#define vi vector<int>
#define vvi vector<vi >
#define vI vector<PII>
#define db double
#define all(a) (a).begin(),(a).end()
#define lowbit(x) (x)&(-x)
#define die cout << "???" << endl
//#define endl '\n'
using namespace std;
const int mod = 998244353;
//const int mod = 1169996969;
//const int mod = 1e9 + 7;
//const int inf = LLONG_MAX;
const int inf = 0x3f3f3f3f;
//const int inf = 1e9;
//const db PI = acos(-1.0);
const db eps = 1e-7;
typedef long long ll;
typedef unsigned long long ull;
const int N = 1e7+5,M = 2e6+5,K = 20;
inline int rd() {
int f = 0; int x = 0; char ch = getchar();
for (; !isdigit(ch); ch = getchar()) f |= (ch == '-');
for (; isdigit(ch); ch = getchar()) x = (x << 1) + (x << 3) + ch - '0';
if (f) x = -x;
return x;
}
void write(ll a) {if(a>=10)write(a/10);putchar(a%10+'0');}
void wt(ll a) {if(a < 0) {putchar('-');a = -a;}write(a);}
void wwt(ll a){wt(a);putchar('\n');}
// int mul(int x, int y, int p)
// {
// int z = (long double)x / p * y;
// ll res = (unsigned long long)x * y - (unsigned long long) z * p;
// return (res + p) % p;
// }
int n,m,k;
template<class T> inline bool smin(T &x,T y) {return x > y?x = y,1:0;}
template<class T> inline bool smax(T &x,T y) {return x < y?x = y,1:0;}
inline int add(int x,int y) {return x + y >= mod?x + y - mod:x+y;}
int fac[N],invf[N];
int fsm(int b,int p)
{
int res = 1;
while(p)
{
if(p&1) res = res*b%mod;
b = b*b%mod;
p >>= 1;
}
return res;
}
signed main()
{
ios::sync_with_stdio(0);
cin.tie(0),cout.tie(0);
#ifndef ONLINE_JUDGE
freopen("in.txt", "r+", stdin);
freopen("out.txt", "w+", stdout);
#endif
fac[0] = fac[1] = 1;
invf[0] = invf[1] = 1;
for(int i = 2;i<N;i++)
{
fac[i] = fac[i-1]*i%mod;
}
invf[N-1] = fsm(fac[N-1],mod-2);
for(int i = N-2;i;i--)
{
invf[i] = invf[i+1]*(i+1)%mod;
}
cin >> n;
int ans = 0;
for(int i = 1;n - i >= i - 1;i++)
{
int tmp = fac[n-i]*fac[n-i]%mod*invf[n+1 - i*2]%mod;
ans = add(ans,tmp);
}
cout << ans;
return 0;
}
// 26 26
// 34 34
// 23 36
// 34 43
// 31 31
詳細信息
Test #1:
score: 100
Accepted
time: 71ms
memory: 159820kb
input:
1
output:
1
result:
ok 1 number(s): "1"
Test #2:
score: 0
Accepted
time: 71ms
memory: 159640kb
input:
2
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 80ms
memory: 159804kb
input:
10
output:
997920
result:
ok 1 number(s): "997920"
Test #4:
score: 0
Accepted
time: 77ms
memory: 159856kb
input:
100
output:
188898954
result:
ok 1 number(s): "188898954"
Test #5:
score: 0
Accepted
time: 61ms
memory: 159808kb
input:
4
output:
10
result:
ok 1 number(s): "10"
Test #6:
score: 0
Accepted
time: 84ms
memory: 159852kb
input:
8
output:
12336
result:
ok 1 number(s): "12336"
Test #7:
score: 0
Accepted
time: 63ms
memory: 159628kb
input:
16
output:
373118483
result:
ok 1 number(s): "373118483"
Test #8:
score: 0
Accepted
time: 78ms
memory: 159692kb
input:
32
output:
314585464
result:
ok 1 number(s): "314585464"
Test #9:
score: 0
Accepted
time: 84ms
memory: 159648kb
input:
64
output:
627827331
result:
ok 1 number(s): "627827331"
Test #10:
score: 0
Accepted
time: 78ms
memory: 159712kb
input:
128
output:
828497685
result:
ok 1 number(s): "828497685"
Test #11:
score: 0
Accepted
time: 58ms
memory: 159696kb
input:
256
output:
65697890
result:
ok 1 number(s): "65697890"
Test #12:
score: 0
Accepted
time: 84ms
memory: 159684kb
input:
512
output:
854187619
result:
ok 1 number(s): "854187619"
Test #13:
score: 0
Accepted
time: 63ms
memory: 159696kb
input:
1024
output:
513823539
result:
ok 1 number(s): "513823539"
Test #14:
score: 0
Accepted
time: 89ms
memory: 159780kb
input:
1361956
output:
617368199
result:
ok 1 number(s): "617368199"
Test #15:
score: 0
Accepted
time: 106ms
memory: 159720kb
input:
7579013
output:
827172636
result:
ok 1 number(s): "827172636"
Test #16:
score: 0
Accepted
time: 105ms
memory: 159720kb
input:
8145517
output:
710624331
result:
ok 1 number(s): "710624331"
Test #17:
score: 0
Accepted
time: 99ms
memory: 159824kb
input:
6140463
output:
707600568
result:
ok 1 number(s): "707600568"
Test #18:
score: 0
Accepted
time: 64ms
memory: 159788kb
input:
3515281
output:
698302413
result:
ok 1 number(s): "698302413"
Test #19:
score: 0
Accepted
time: 87ms
memory: 159776kb
input:
6969586
output:
69470392
result:
ok 1 number(s): "69470392"
Test #20:
score: 0
Accepted
time: 92ms
memory: 159696kb
input:
2888636
output:
433579983
result:
ok 1 number(s): "433579983"
Test #21:
score: 0
Accepted
time: 89ms
memory: 159700kb
input:
9999998
output:
758172780
result:
ok 1 number(s): "758172780"
Test #22:
score: 0
Accepted
time: 85ms
memory: 159684kb
input:
9999999
output:
605195495
result:
ok 1 number(s): "605195495"
Test #23:
score: 0
Accepted
time: 84ms
memory: 159680kb
input:
10000000
output:
866813682
result:
ok 1 number(s): "866813682"