#include #include "testlib.h" using namespace std; #define int long long const int MOD=1e9+7; const int MIN_N=1,MAX_N=100000; const int MIN_K=0,MAX_K=200000; int pw(int n,int k){ if(k<0)return pw(n,k+MOD-1); int res=1; while(k){ if(k&1)res*=n;res%=MOD; n*=n;n%=MOD; k>>=1; } return res; } std::vector Factorial(5e6),Finverse(5e6); inline void Cinit(){// limit is 5e6 /// write pw /// this takes 792ms at AtCoder Factorial[0]=1; for(int i=1;i<5e6;i++)Factorial[i]=Factorial[i-1]*i%MOD; for(int i=0;i<5e6;i++)Finverse[i]=pw(Factorial[i],MOD-2); } int nCk(int n,int k){ if(n>=1; int res=nCk(n,a)*nCk(m,a)%MOD; res*=Factorial[n-1]*Factorial[m-1]%MOD;res%=MOD; return res*a%MOD; } signed main(){ registerValidation(); int a=inf.readLong(MIN_N,MAX_N); inf.readSpace(); m=inf.readLong(MIN_N,MAX_N); inf.readSpace(); k=inf.readLong(MIN_K,MAX_K); inf.readEoln(); ensuref(k<=n+m,"k<=n+m"); int ans=0; for(int i=0;i<=n+m-k;i++)ans+=f(i),ans%=MOD; cout<