#include <iostream>
#include <vector>
using namespace std;
typedef long long ll;

const ll MOD = 1000000007;

ll modpow(ll x, ll n){
    ll res = 1;
    ll mul = x;
    while(n){
        if(n % 2) res = res * mul % MOD;
        mul = mul * mul % MOD;
        n /= 2;
    }
    return res;
}

struct Combination
{
    int maxn;
    vector<ll> fmemo;
    vector<ll> imemo;
    vector<ll> ifmemo;
    
    Combination(int maxn) : maxn(maxn){
        fmemo.resize(maxn + 1);
        imemo.resize(maxn + 1);
        ifmemo.resize(maxn + 1);
        for(ll i = 1; i <= maxn; i++){
            imemo[i] = modpow(i, MOD - 2);
        }
    }

    ll fact(ll n){
        if(n == 0) return 1;
        if(fmemo[n]) return fmemo[n];
        return fmemo[n] = n * fact(n - 1) % MOD;
    }

    ll ifact(ll n){
        if(n == 0) return 1;
        if(ifmemo[n]) return ifmemo[n];
        return ifmemo[n] = imemo[n] * ifact(n - 1) % MOD;
    }

    ll com(ll n, ll k){
        if(k > n) return 0;
        if(k == n || k == 0) return 1;
        return (fact(n) * ifact(k) % MOD) * ifact(n - k) % MOD;
    }
};

int main()
{
    int n, m, k;
    cin >> n >> m >> k;
    Combination com(n * m);
    ll c = com.com(n * m - 2, k - 2);
    ll ans = 0;
    for(int i = 0; i < n; i++){
        for(int j = 0; j < m; j++){
            if(i + j == 0) continue;
            if(i == 0 || j == 0) ans = (ans + c * (i + j) % MOD * (n - i) * (m - j) % MOD) % MOD;
            else ans = (ans + c * (i + j) % MOD * (n - i) * (m - j) * 2 % MOD) % MOD;
        }
    }
    cout << ans << endl;
}

#include <bits/stdc++.h>

using namespace std;

const int N=2e5+5,MOD=1e9+7;

long long fac[N],infac[N];

long long poww(long long x,long long y)
{
	if(y==0) return 1;
	if(y&1) return (x*poww(x,y-1))%MOD;
	return poww((x*x)%MOD,y/2);
}

long long nck(int n,int k)
{
	return (((fac[n]*infac[k])%MOD)*infac[n-k])%MOD;
}

long long get(int a,int b,int c,int d)
{
	int tot=(c-a)+(d-b);
	return nck(tot,c-a);
}

int main()
{
	fac[0]=infac[0]=1;
	for(int i=1;i<N;i++)
	{
		fac[i]=(fac[i-1]*i)%MOD;
		infac[i]=poww(fac[i],MOD-2);
	}
	int n,m,a,b;
	cin >> n >> m >> a >> b;
	long long ans=0;
	for(int i=0;i<n-a;i++)
	{
		ans+=get(0,0,i,b-1)*get(i,b,n-1,m-1);
		ans%=MOD;
	}
	cout << ans << endl;
}