#include <bits/stdc++.h> using namespace std; const int mod = 1e9 + 7; int cnm(int n,int m) { if(n==1) return m; return m*cnm(n-1, m-1)/n; } int main() { int n,m,k; cin>>n>>m>>k; cout<<(cnm(k*2,n-1)*cnm(k*2,m-1)) % mod; }
Cn−12k×Cm−12kC_{n-1}^{2k} \times C_{m-1}^{2k} Cn−12k×Cm−12k