#include #include #include using namespace std; //cin, coutを使う long long big_num = 998244353 ; const long long MAX = 1000005; const long long MOD = 998244353; std::vector fac, finv, inv; // テーブルを作る前処理 void COMinit() { fac.resize(MAX); finv.resize(MAX); inv.resize(MAX); fac[0] = fac[1] = 1; finv[0] = finv[1] = 1; inv[1] = 1; for (int i = 2; i < MAX; i++){ fac[i] = fac[i - 1] * i % MOD; inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD; finv[i] = finv[i - 1] * inv[i] % MOD; } } // 二項係数計算 long long COM(int n, int k){ if (n < k) return 0; if (n < 0 || k < 0) return 0; return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD; } int min_x (int a, int b){ if (a < b) { return a; } else { return b; } } int Cx(int a, int b){ long long i = 1; for (int h = 0; h < b; h++){ i *= (a - h); i /= (b - h); } if (i > big_num) i %= big_num; return (int)i; }; int main(){ long long H, W, K; COMinit(); long long ret = 0; for (int i = 1; i <= K; i++ ){ if (i > H) break; if (K % i != 0) continue; if ((int)(K / i) > W) continue; long long hi = COM(H, i); if (hi > big_num) hi %= big_num; long long wk_i = COM(W, (int)(K / i)); if (wk_i > big_num) wk_i %= big_num; ret += hi * wk_i; if (ret > big_num) ret %= big_num; } cout << ret << endl; return 0; };