ConstructTheArrayDP

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.regex.*;

public class Solution {

    // Complete the countArray function below.
    static long countArray(int n, int k, int x) {

        final long MOD = 1000000007;

        long[] a = new long[n];
        long[] b = new long[n];

        a[0] = x == 1 ? 1 : 0;
        b[0] = x == 1 ? 0 : 1;

        //O(n) time and space
        for (int i = 1; i < n; i++) {
            a[i] = b[i-1] % MOD;
            b[i] = (a[i - 1] * (k - 1) + b[i - 1] * (k - 2)) % MOD;
        }

        return a[n-1];

    }

    private static final Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) throws IOException {

        String[] nkx = scanner.nextLine().split(" ");

        int n = Integer.parseInt(nkx[0]);

        int k = Integer.parseInt(nkx[1]);

        int x = Integer.parseInt(nkx[2]);

        long answer = countArray(n, k, x);

        System.out.println(answer);

        scanner.close();
    }
}