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nCr
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nCr
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#include<bits/stdc++.h>
using namespace std;
const int N = 3e5 + 9, mod = 1e9 + 7;
template <const int32_t MOD>
struct modint {
int32_t value;
modint() = default;
modint(int32_t value_) : value(value_) {}
inline modint<MOD> operator + (modint<MOD> other) const { int32_t c = this->value + other.value; return modint<MOD>(c >= MOD ? c - MOD : c); }
inline modint<MOD> operator - (modint<MOD> other) const { int32_t c = this->value - other.value; return modint<MOD>(c < 0 ? c + MOD : c); }
inline modint<MOD> operator * (modint<MOD> other) const { int32_t c = (int64_t)this->value * other.value % MOD; return modint<MOD>(c < 0 ? c + MOD : c); }
inline modint<MOD> & operator += (modint<MOD> other) { this->value += other.value; if (this->value >= MOD) this->value -= MOD; return *this; }
inline modint<MOD> & operator -= (modint<MOD> other) { this->value -= other.value; if (this->value < 0) this->value += MOD; return *this; }
inline modint<MOD> & operator *= (modint<MOD> other) { this->value = (int64_t)this->value * other.value % MOD; if (this->value < 0) this->value += MOD; return *this; }
inline modint<MOD> operator - () const { return modint<MOD>(this->value ? MOD - this->value : 0); }
modint<MOD> pow(uint64_t k) const { modint<MOD> x = *this, y = 1; for (; k; k >>= 1) { if (k & 1) y *= x; x *= x; } return y; }
modint<MOD> inv() const { return pow(MOD - 2); } // MOD must be a prime
inline modint<MOD> operator / (modint<MOD> other) const { return *this * other.inv(); }
inline modint<MOD> operator /= (modint<MOD> other) { return *this *= other.inv(); }
inline bool operator == (modint<MOD> other) const { return value == other.value; }
inline bool operator != (modint<MOD> other) const { return value != other.value; }
inline bool operator < (modint<MOD> other) const { return value < other.value; }
inline bool operator > (modint<MOD> other) const { return value > other.value; }
};
template <int32_t MOD> modint<MOD> operator * (int64_t value, modint<MOD> n) { return modint<MOD>(value) * n; }
template <int32_t MOD> modint<MOD> operator * (int32_t value, modint<MOD> n) { return modint<MOD>(value % MOD) * n; }
template <int32_t MOD> istream & operator >> (istream & in, modint<MOD> &n) { return in >> n.value; }
template <int32_t MOD> ostream & operator << (ostream & out, modint<MOD> n) { return out << n.value; }
using mint = modint<mod>;
struct combi{
int n; vector<mint> facts, finvs, invs;
combi(int _n): n(_n), facts(_n), finvs(_n), invs(_n){
facts[0] = finvs[0] = 1;
invs[1] = 1;
for (int i = 2; i < n; i++) invs[i] = invs[mod % i] * (-mod / i);
for(int i = 1; i < n; i++){
facts[i] = facts[i - 1] * i;
finvs[i] = finvs[i - 1] * invs[i];
}
}
inline mint fact(int n) { return facts[n]; }
inline mint finv(int n) { return finvs[n]; }
inline mint inv(int n) { return invs[n]; }
inline mint ncr(int n, int k) { return n < k or k < 0 ? 0 : facts[n] * finvs[k] * finvs[n-k]; }
};
combi C(N);
int32_t main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout << C.ncr(10, 2) << '\n';
return 0;
}