#include <iostream>

long int numArrays(long int n, long int k, long int x) {
	return (n - 3) * (k - 1) + (k - 2);
}

int main() {
	long int n, k, x;
	std::cin >> n >> k >> x;
	std::cout <<  numArrays(n, k, x) % 1000000007 << std::endl;

	return 0;
}