N,S,B = map(int,input().split())
H = list(map(int,input().split()))
h = H[0]
s = S
F = True
for i in range(N):
    if H[i] >= h:
        if H[i]-h > s*B:
            F = False
            break
        h = H[i]
        s = S
print('Yes' if F else 'No')