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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
#168983#6417. Classical Summation ProblemfryanWA 87ms135144kbC++203.0kb2023-09-09 09:54:322023-09-09 09:54:34

Judging History

你现在查看的是最新测评结果

  • [2023-09-09 09:54:34]
  • 评测
  • 测评结果:WA
  • 用时:87ms
  • 内存:135144kb
  • [2023-09-09 09:54:32]
  • 提交

answer

// Problem: A - W1P1: XOR Clique
// Contest: Virtual Judge - 602 - Season 2023 - HW Series 2
// URL: https://vjudge.net/contest/580028#problem/A
// Memory Limit: 253 MB
// Time Limit: 1000 ms
// 
// Powered by CP Editor (https://cpeditor.org)


#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <cctype>
#include <cfenv>
#include <cfloat>
#include <chrono>
#include <cinttypes>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdarg>
#include <cstddef>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <deque>
#include <fstream>
#include <functional>
#include <immintrin.h>
#include <initializer_list>
#include <iomanip>
#include <ios>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <streambuf>
#include <string>
#include <tuple>
#include <type_traits>
#include <variant>
using namespace std;

//numbers
using ll=long long;
#define int ll
using ld=long double;
//pairs
#define P pair
#define pi P<int,int>
#define ff first
#define ss second
#define mp make_pair
//std data structure
#define all(x) begin(x), end(x)
#define sz(x) (int) (x).size()
//vectors
#define V vector
#define vi V<int>
#define v2i V<vi>
#define v3i V<v2i>
#define vpi V<pi>
#define vsi V<si>
#define pb push_back
//sets
#define S set
#define MS multiset
#define US unordered_set
#define si S<int>
#define msi MS<int>
#define usi US<int>
#define ins insert
#define era erase
//maps
#define M map
#define UM unordered_map
#define mii M<int,int>
#define mivi UM<int,vi>
#define misi UM<int,si>
#define umii UM<int,int>
#define umivi UM<int,vi>
#define umisi UM<int,si>
//queues
#define Q queue
#define PQ priority_queue
#define qi Q<int>
#define qpi Q<pi>
#define pqi PQ<int>
#define rpqi PQ<int,vi,greater<int> >
#define pqpi PQ<pi>
#define rpqpi PQ<pi,vpi,greater<pi> >
//constants
const int MOD=998244353;
const int INF=922337203685477580;
//nt functions
int binpow(int a, int b, int m=MOD) {
    a%=m; int res=1;
    while (b>0) {
        if (b&1) res=res*a%m;
        a=a*a%m;
        b>>=1;
    }
    return res;
}
int gcd (int a, int b) {
    return b?gcd (b,a%b):a;
}
int lcm (int a, int b) {
    return a/gcd(a,b)*b;
}
int inv(int i, int m=MOD) {
	return binpow(i, m-2, m);
}
vi f;
void fs() {
	f.pb(1);
	for (int i=1; i<1e7; i++) {
		f.pb(i*f[i-1]); f[i]%=MOD;
	}
}
int comb(int n, int k) {
	return ((f[n]*inv(f[n-k]))%MOD*inv(f[k]))%MOD;
}
//new header wip

signed main() {
	ios::sync_with_stdio(false); cin.tie(nullptr);
	int n,k; cin>>n>>k;
	if (k%2) {cout<<(n+1)/2*binpow(n,k); return 0;}
	int b=0; fs();
	for (int i=0; i<n; i++) {
		b+=((comb(k,k/2)*binpow(i,k/2))%MOD*binpow(n-i,k/2))%MOD;
		b%=MOD;
	}
	cout<<(n+1)/2*binpow(n,k)-b/2;
	
	return 0;
}

详细

Test #1:

score: 100
Accepted
time: 87ms
memory: 134864kb

input:

3 2

output:

14

result:

ok 1 number(s): "14"

Test #2:

score: 0
Accepted
time: 1ms
memory: 3668kb

input:

5 3

output:

375

result:

ok 1 number(s): "375"

Test #3:

score: -100
Wrong Answer
time: 73ms
memory: 135144kb

input:

2 2

output:

3

result:

wrong answer 1st numbers differ - expected: '5', found: '3'