#https://www.hackerrank.com/contests/101hack52/challenges/construct-the-array   
                                                                                
MOD = 1000000007                                                                
                                                                                
if __name__ == "__main__":                                                      
    n, k, x = [int(_) for _ in input().strip().split()]                         
    if x == 1:                                                                  
        p = k-1                                                                 
    else:                                                                       
        p = k-2                                                                 
    total = k-1                                                                 
    for i in range(2,n-1):                                                      
        total = (total * (k-1)) % MOD                                           
        p = (total - p) % MOD                                                   
    print(p)