#925491 (C++14) No.2527 H and W

• 問題: No.2527 H and W
• ユーザー: umimel
• 提出日時: 2023-11-03 21:46:48
• 言語: C++14 (gcc 12.3.0 + boost 1.83.0)
• 結果: AC
• 実行時間: 301 ms / 2,000 ms
• コード長: 3,298 bytes
• コンパイル時間: 1,564 ms
• コンパイル使用メモリ: 169,328 KB
• 実行使用メモリ: 27,056 KB
• 最終ジャッジ日時: 2023-11-03 21:46:59
• 合計ジャッジ時間: 9,964 ms
• ジャッジサーバーID （参考情報）: judge10 / judge14

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	272 ms; 27,056 KB
testcase_01	AC	266 ms; 27,056 KB
testcase_02	AC	280 ms; 27,056 KB
testcase_03	AC	271 ms; 27,056 KB
testcase_04	AC	280 ms; 27,056 KB
testcase_05	AC	282 ms; 27,056 KB
testcase_06	AC	301 ms; 27,056 KB
testcase_07	AC	269 ms; 27,056 KB
testcase_08	AC	279 ms; 27,056 KB
testcase_09	AC	263 ms; 27,056 KB
testcase_10	AC	271 ms; 27,056 KB
testcase_11	AC	280 ms; 27,056 KB
testcase_12	AC	282 ms; 27,056 KB
testcase_13	AC	282 ms; 27,056 KB
testcase_14	AC	272 ms; 27,056 KB
testcase_15	AC	279 ms; 27,056 KB
testcase_16	AC	295 ms; 27,056 KB
testcase_17	AC	278 ms; 27,056 KB
testcase_18	AC	274 ms; 27,056 KB
testcase_19	AC	268 ms; 27,056 KB
testcase_20	AC	273 ms; 27,056 KB
testcase_21	AC	294 ms; 27,056 KB
testcase_22	AC	274 ms; 27,056 KB
testcase_23	AC	273 ms; 27,056 KB
testcase_24	AC	264 ms; 27,056 KB
testcase_25	AC	260 ms; 27,056 KB

ソースコード

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
using pll = pair<ll, ll>;
#define drep(i, cc, n) for (ll i = (cc); i <= (n); ++i)
#define rep(i, n) drep(i, 0, n - 1)
#define all(a) (a).begin(), (a).end()
#define pb push_back
#define fi first
#define se second
mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());
const ll MOD1000000007 = 1000000007;
const ll MOD998244353 = 998244353;
const ll MOD[3] = {999727999, 1070777777, 1000000007};
const ll LINF = 1LL << 60LL;
const int IINF = (1 << 30) - 1;


template<long long mod>
class modint{
    long long x;
public:
    modint(long long x=0) : x((x%mod+mod)%mod) {}
    modint operator-() const { 
      return modint(-x);
    }
    bool operator==(const modint& a){
        if(x == a) return true;
        else return false;
    }
    bool operator==(long long a){
        if(x == a) return true;
        else return false;
    }
    bool operator!=(const modint& a){
        if(x != a) return true;
        else return false;
    }
    bool operator!=(long long a){
        if(x != a) return true;
        else return false;
    }
    modint& operator+=(const modint& a) {
        if ((x += a.x) >= mod) x -= mod;
        return *this;
    }
    modint& operator-=(const modint& a) {
        if ((x += mod-a.x) >= mod) x -= mod;
        return *this;
    }
    modint& operator*=(const  modint& a) {
        (x *= a.x) %= mod;
        return *this;
    }
    modint operator+(const modint& a) const {
        modint res(*this);
        return res+=a;
    }
    modint operator-(const modint& a) const {
        modint res(*this);
        return res-=a;
    }
    modint operator*(const modint& a) const {
        modint res(*this);
        return res*=a;
    }
    modint pow(long long t) const {
        if (!t) return 1;
        modint a = pow(t>>1);
        a *= a;
        if (t&1) a *= *this;
        return a;
    }
    // for prime mod
    modint inv() const {
        return pow(mod-2);
    }
    modint& operator/=(const modint& a) {
        return (*this) *= a.inv();
    }
    modint operator/(const modint& a) const {
        modint res(*this);
        return res/=a;
    }

    friend std::istream& operator>>(std::istream& is, modint& m) noexcept {
        is >> m.x;
        m.x %= mod;
        if (m.x < 0) m.x += mod;
        return is;
    }

    friend ostream& operator<<(ostream& os, const modint& m){
        os << m.x;
        return os;
    }
};

using mint = modint<MOD998244353>;

const ll MAX = 1000001;
mint fac[MAX], finv[MAX], inv[MAX];
 
void cominit(){
    fac[0] = fac[1] = 1;
    finv[0] = finv[1] = 1;
    inv[1] = 1;
    for(ll i=2; i<MAX; i++){
        fac[i] = fac[i-1] * i;
        inv[i] = mint(i).inv();
        finv[i] = finv[i-1] * inv[i];
    }
}
 
mint com(ll n, ll k){
    if(n < k) return 0;
    if(n < 0 || k < 0) return mint(0);
    return fac[n] * finv[k] * finv[n-k];
}

void solve(){
    ll H, W, K; cin >> H >> W >> K;
    cominit();
    mint ans = 0;
    for(ll x=0; x<H; x++){
        if((H*W-K-x*W)%(H-x)!=0) continue;
        ll y = (H*W-K-x*W)/(H-x);

        ans += com(H, x)*com(W, y);
    }

    cout << ans << endl;
}

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    
    int T=1;
    //cin >> T;
    while(T--) solve();
}