Contest Duration: - (local time) (160 minutes) Back to Home

Submission #6539243

Source Code Expand

Copy
```#include <algorithm>
#include <bitset>
#include <cassert>
#include <cctype>
#include <chrono>
#define _USE_MATH_DEFINES
#include <cmath>
#include <cstdio>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iostream>
#include <iterator>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <tuple>
#include <utility>
#include <vector>
using namespace std;

#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()

const int INF = 0x3f3f3f3f;
const long long LINF = 0x3f3f3f3f3f3f3f3fLL;
const double EPS = 1e-8;
const int MOD = 998244353;
const int dy[] = {1, 0, -1, 0}, dx[] = {0, -1, 0, 1};
/*-------------------------------------------------*/
long long mod_inv(long long a, long long mod = MOD) {
a %= mod;
if (__gcd(a, mod) != 1) return -1;
long long b = mod, x = 1, y = 0;
while (b > 0) {
long long tmp = a / b;
a -= tmp * b;
swap(a, b);
x -= tmp * y;
swap(x, y);
}
x %= mod;
if (x < 0) x += mod;
return x;
}

const int MAX = 10000000;
long long fact[MAX + 1], fact_inv[MAX + 1];
void nCk_init(int val = MAX, long long mod = MOD) {
fact[0] = 1;
FOR(i, 1, val + 1) fact[i] = fact[i - 1] * i % mod;
fact_inv[val] = mod_inv(fact[val], mod);
for (int i = val; i > 0; --i) fact_inv[i - 1] = fact_inv[i] * i % mod;
}

long long nCk(int n, int k, long long mod = MOD) {
if (n < 0 || n < k || k < 0) return 0;
return fact[n] * fact_inv[k] % mod * fact_inv[n - k] % mod;
}

int main() {
cin.tie(0); ios::sync_with_stdio(false);
// freopen("input.txt", "r", stdin);

nCk_init();
int n, m; cin >> n >> m;
long long ans = 0;
REP(i, min(n, m) + 1) {
int gp = 3 * m - i;
if (gp & 1) continue;
gp /= 2;
(ans += nCk(n, i) * nCk(gp + n - 1, n - 1) % MOD) %= MOD;
}
long long tmp = 0;
REP(i, m) (tmp += nCk(i + n - 2, n - 2)) %= MOD;
(tmp *= n) %= MOD;
ans -= tmp;
if (ans < 0) ans += MOD;
cout << ans << '\n';
return 0;
}
```

#### Submission Info

Submission Time 2019-07-26 03:10:33+0900 C - GP 2 emthrm C++14 (GCC 5.4.1) 900 2133 Byte AC 353 ms 156544 KB

#### Judge Result

Set Name Sample All
Score / Max Score 0 / 0 900 / 900
Status
 AC × 4
 AC × 26
Set Name Test Cases
Sample sample-01.txt, sample-02.txt, sample-03.txt, sample-04.txt
All 01-01.txt, 01-02.txt, 01-03.txt, 01-04.txt, 01-05.txt, 01-06.txt, 01-07.txt, 01-08.txt, 01-09.txt, 01-10.txt, 01-11.txt, 01-12.txt, 01-13.txt, 01-14.txt, 01-15.txt, 01-16.txt, 01-17.txt, 01-18.txt, 01-19.txt, 01-20.txt, 01-21.txt, 01-22.txt, sample-01.txt, sample-02.txt, sample-03.txt, sample-04.txt
Case Name Status Exec Time Memory
01-01.txt AC 327 ms 156544 KB
01-02.txt AC 343 ms 156544 KB
01-03.txt AC 328 ms 156544 KB
01-04.txt AC 336 ms 156544 KB
01-05.txt AC 332 ms 156544 KB
01-06.txt AC 336 ms 156544 KB
01-07.txt AC 341 ms 156544 KB
01-08.txt AC 337 ms 156544 KB
01-09.txt AC 335 ms 156544 KB
01-10.txt AC 349 ms 156544 KB
01-11.txt AC 350 ms 156544 KB
01-12.txt AC 352 ms 156544 KB
01-13.txt AC 333 ms 156544 KB
01-14.txt AC 339 ms 156544 KB
01-15.txt AC 334 ms 156544 KB
01-16.txt AC 353 ms 156544 KB
01-17.txt AC 327 ms 156544 KB
01-18.txt AC 327 ms 156544 KB
01-19.txt AC 326 ms 156544 KB
01-20.txt AC 338 ms 156544 KB
01-21.txt AC 338 ms 156544 KB
01-22.txt AC 339 ms 156544 KB
sample-01.txt AC 326 ms 156544 KB
sample-02.txt AC 327 ms 156544 KB
sample-03.txt AC 326 ms 156544 KB
sample-04.txt AC 329 ms 156544 KB