#ifndef HIDDEN_IN_VS // 折りたたみ用 // 警告の抑制 #define _CRT_SECURE_NO_WARNINGS // ライブラリの読み込み #include using namespace std; // 型名の短縮 using ll = long long; // -2^63 ~ 2^63 = 9 * 10^18(int は -2^31 ~ 2^31 = 2 * 10^9) using pii = pair; using pll = pair; using pil = pair; using pli = pair; using vi = vector; using vvi = vector; using vvvi = vector; using vl = vector; using vvl = vector; using vvvl = vector; using vb = vector; using vvb = vector; using vvvb = vector; using vc = vector; using vvc = vector; using vvvc = vector; using vd = vector; using vvd = vector; using vvvd = vector; template using priority_queue_rev = priority_queue, greater>; using Graph = vvi; // 定数の定義 const double PI = acos(-1); const vi DX = { 1, 0, -1, 0 }; // 4 近傍(下,右,上,左) const vi DY = { 0, 1, 0, -1 }; int INF = 1001001001; ll INFL = 4004004004004004004LL; double EPS = 1e-12; // 入出力高速化 struct fast_io { fast_io() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(18); } } fastIOtmp; // 汎用マクロの定義 #define all(a) (a).begin(), (a).end() #define sz(x) ((int)(x).size()) #define lbpos(a, x) (int)distance((a).begin(), std::lower_bound(all(a), x)) #define ubpos(a, x) (int)distance((a).begin(), std::upper_bound(all(a), x)) #define Yes(b) {cout << ((b) ? "Yes\n" : "No\n");} #define rep(i, n) for(int i = 0, i##_len = int(n); i < i##_len; ++i) // 0 から n-1 まで昇順 #define repi(i, s, t) for(int i = int(s), i##_end = int(t); i <= i##_end; ++i) // s から t まで昇順 #define repir(i, s, t) for(int i = int(s), i##_end = int(t); i >= i##_end; --i) // s から t まで降順 #define repe(v, a) for(const auto& v : (a)) // a の全要素(変更不可能) #define repea(v, a) for(auto& v : (a)) // a の全要素(変更可能) #define repb(set, d) for(int set = 0; set < (1 << int(d)); ++set) // d ビット全探索(昇順) #define repp(a) sort(all(a)); for(bool a##_perm = true; a##_perm; a##_perm = next_permutation(all(a))) // a の順列全て(昇順) #define smod(n, m) ((((n) % (m)) + (m)) % (m)) // 非負mod #define uniq(a) {sort(all(a)); (a).erase(unique(all(a)), (a).end());} // 重複除去 #define EXIT(a) {cout << (a) << endl; exit(0);} // 強制終了 // 汎用関数の定義 template inline ll pow(T n, int k) { ll v = 1; rep(i, k) v *= n; return v; } template inline bool chmax(T& M, const T& x) { if (M < x) { M = x; return true; } return false; } // 最大値を更新(更新されたら true を返す) template inline bool chmin(T& m, const T& x) { if (m > x) { m = x; return true; } return false; } // 最小値を更新(更新されたら true を返す) // 演算子オーバーロード template inline istream& operator>>(istream& is, pair& p) { is >> p.first >> p.second; return is; } template inline istream& operator>>(istream& is, vector& v) { repea(x, v) is >> x; return is; } template inline vector& operator--(vector& v) { repea(x, v) --x; return v; } template inline vector& operator++(vector& v) { repea(x, v) ++x; return v; } // 手元環境(Visual Studio) #ifdef _MSC_VER #include "local.hpp" // 提出用(gcc) #else inline int popcount(int n) { return __builtin_popcount(n); } inline int popcount(ll n) { return __builtin_popcountll(n); } inline int lsb(int n) { return n != 0 ? __builtin_ctz(n) : -1; } inline int lsb(ll n) { return n != 0 ? __builtin_ctzll(n) : -1; } inline int msb(int n) { return n != 0 ? (31 - __builtin_clz(n)) : -1; } inline int msb(ll n) { return n != 0 ? (63 - __builtin_clzll(n)) : -1; } #define gcd __gcd #define dump(...) #define dumpel(v) #define dump_list(v) #define dump_list2D(v) #define input_from_file(f) #define output_to_file(f) #define Assert(b) { if (!(b)) while (1) cout << "OLE"; } #endif #endif // 折りたたみ用 #if __has_include() #include using namespace atcoder; using mint = modint1000000007; //using mint = modint998244353; //using mint = modint; // mint::set_mod(m); istream& operator>>(istream& is, mint& x) { ll x_; is >> x_; x = x_; return is; } ostream& operator<<(ostream& os, const mint& x) { os << x.val(); return os; } using vm = vector; using vvm = vector; using vvvm = vector; #endif //【階乗など(法が大きな素数)】 /* * Factorial_mint(int n_max) : O(n_max) * n_max! まで計算可能として初期化する. * * mint factorial(int n) : O(1) * n! を返す. * * mint factorial_inv(int n) : O(1) * 1 / n! を返す. * * mint inv(int n) : O(1) * 1 / n を返す. * * mint permutation(int n, int r) : O(1) * 順列の数 nPr を返す. * * mint binomial(int n, int r) : O(1) * 二項係数 nCr を返す. * * mint multinomial(vi rs) : O(|rs|) * 多項係数 nC[rs] を返す.(n = Σrs) */ class Factorial_mint { // 階乗,階乗の逆数,逆数の値を保持するテーブル int n_max; vm fac, fac_inv; public: // n! までの階乗とその逆数を前計算しておく.O(n) Factorial_mint(int n) : n_max(n), fac(n + 1), fac_inv(n + 1) { // verify : https://atcoder.jp/contests/dwacon6th-prelims/tasks/dwacon6th_prelims_b fac[0] = 1; repi(i, 1, n) fac[i] = fac[i - 1] * i; fac_inv[n] = fac[n].inv(); repir(i, n - 1, 0) fac_inv[i] = fac_inv[i + 1] * (i + 1); } Factorial_mint() : n_max(0) {} // ダミー // n! を返す.O(1) mint factorial(int n) const { // verify : https://atcoder.jp/contests/dwacon6th-prelims/tasks/dwacon6th_prelims_b Assert(0 <= n && n <= n_max); return fac[n]; } // 1 / n! を返す.O(1) mint factorial_inv(int n) const { // verify : https://atcoder.jp/contests/dwacon6th-prelims/tasks/dwacon6th_prelims_b Assert(0 <= n && n <= n_max); return fac_inv[n]; } // 1 / n を返す.O(1) mint inv(int n) const { // verify : https://atcoder.jp/contests/exawizards2019/tasks/exawizards2019_d Assert(0 < n && n <= n_max); return fac[n - 1] * fac_inv[n]; } // 順列の数 nPr を返す.O(1) mint permutation(int n, int r) const { Assert(n <= n_max); if (r < 0 || n - r < 0) return 0; return fac[n] * fac_inv[n - r]; } // 二項係数 nCr を返す.O(1) mint binomial(int n, int r) const { // verify : https://atcoder.jp/contests/abc034/tasks/abc034_c Assert(n <= n_max); if (r < 0 || n - r < 0) return 0; return fac[n] * fac_inv[r] * fac_inv[n - r]; } // 多項係数 nC[r] を返す.O(|r|) mint multinomial(const vi& rs) const { // verify : https://yukicoder.me/problems/no/2141 if (*min_element(all(rs)) < 0) return 0; int n = accumulate(all(rs), 0); Assert(n <= n_max); mint res = fac[n]; repe(r, rs) res *= fac_inv[r]; return res; } }; mint acc_TLE(int a, int b, int c) { if (a < 0 || b < 0 || c < 0) return 0; Factorial_mint fm(a + b + c); mint res = 0, pow2 = mint(2).pow(max(a, c)); repi(k, max(a, c), a + b + c) { mint coef = ((a + b + c - k) & 1 ? -1 : 1) * pow2 * fm.binomial(k, a); mint sum = 0; repi(l, 0, min(a, b)) { sum += fm.binomial(a, l) * fm.binomial(k - a, b - l) * fm.binomial(a + b - l, a + b + c - k - l); } res += coef * sum; pow2 *= 2; } return res; } mint solve_TLE(int a, int b, int c) { mint res = 0; res += acc_TLE(a, b, c); res -= acc_TLE(a - 1, b, c); res -= acc_TLE(a, b - 1, c); res -= acc_TLE(a, b, c - 1); res += acc_TLE(a - 1, b - 1, c); res += acc_TLE(a - 1, b, c - 1); res += acc_TLE(a, b - 1, c - 1); res -= acc_TLE(a - 1, b - 1, c - 1); return res; } //【畳込み(法が任意)】O((n + m) log (n + m)) /* * a と b の mod を法とした畳込みを返す. */ vi convolution_arbitrary_mod(const vi& a, const vi& b, int mod = (int)1e9 + 7) { // verify : https://judge.yosupo.jp/problem/convolution_mod_1000000007 int n = sz(a), m = sz(b); vl a0(n), a1(n), b0(m), b1(m); const int pow2 = 1 << 15; rep(i, n) { int ai = smod(a[i], mod); a0[i] = ai % pow2; a1[i] = ai / pow2; } rep(i, m) { int bi = smod(b[i], mod); b0[i] = bi % pow2; b1[i] = bi / pow2; } vl c00 = convolution_ll(a0, b0); vl c11 = convolution_ll(a1, b1); rep(i, n) a0[i] += a1[i]; rep(i, m) b0[i] += b1[i]; vl c01 = convolution_ll(a0, b0); rep(i, n + m - 1) { c00[i] %= mod; c11[i] %= mod; c01[i] = (c01[i] - c00[i] - c11[i] + 2LL * mod) % mod; } vi c(n + m - 1); rep(i, n + m - 1) { c[i] = (int)((c00[i] + c01[i] * pow2 + c11[i] * pow2 * pow2) % mod); } return c; } mint acc_TLE2(int a, int b, int c) { if (a < 0 || b < 0 || c < 0) return 0; Factorial_mint fm(2 * (a + b + c)); vi f(a + b + c + 1), g(a + b + c + 1), h(a + b + c + 1); mint pow2 = 1; repi(i, 0, a + b + c) { f[i] = (pow2 * fm.binomial(i, c)).val(); g[i] = (fm.multinomial({ a - i, b - i, i })).val(); h[i] = (fm.binomial(c, i)).val(); // dump(i, f[i], g[i], h[i]); pow2 *= -2; } vi fg = convolution_arbitrary_mod(f, g); mint res = 0; repi(i, 0, a + b + c) res += mint(fg[i]) * h[a + b + c - i]; if ((a + b + c) & 1) res *= -1; return res; } mint solve_TLE2(int a, int b, int c) { mint res = 0; res += acc_TLE2(a, b, c); res -= acc_TLE2(a - 1, b, c); res -= acc_TLE2(a, b - 1, c); res -= acc_TLE2(a, b, c - 1); res += acc_TLE2(a - 1, b - 1, c); res += acc_TLE2(a - 1, b, c - 1); res += acc_TLE2(a, b - 1, c - 1); res -= acc_TLE2(a - 1, b - 1, c - 1); return res; } int main() { // input_from_file("input.txt"); // output_to_file("output.txt"); int a, b, c; cin >> a >> b >> c; dump(solve_TLE(a, b, c)); cout << solve_TLE2(a, b, c) << endl; }