import sys
import math

def solve():
    input_data = sys.stdin.read().split()
    if not input_data:
        return
    N = int(input_data[0])
    W = int(input_data[1])
    
    X = []
    Y = []
    
    idx = 2
    for _ in range(N):
        X.append(int(input_data[idx]))
        idx += 1
    for _ in range(N):
        Y.append(int(input_data[idx]))
        idx += 1
        
    ans = 0
    g = 0
    for i in range(N):
        if X[i] % W == 0:
            g = math.gcd(g, X[i])
            ans += Y[i]
            
    if g == W:
        print(ans)
    else:
        print(0)

if __name__ == '__main__':
    solve()