N,D,T = map(int,raw_input().split())
A = {}
X = map(int,raw_input().split())
for x in X:
    if x%D not in A: A[x%D] = [[x/D-T, x/D+T]]
    else: A[x%D].append([x/D-T,x/D+T])

A = [a for a in A.values()]
B = []
for a in A:
    B.append([a[0]])
    for ai in a[1:]:
        if B[-1][-1][1] >= ai[0]: B[-1][-1][1] = max(B[-1][-1][1],ai[1])
        else: B[-1].append(ai)

ans = sum(sum(bi[1]+1-bi[0] for bi in b) for b in B)
print ans