n, D, T = map(int, input().split())
xs = list(map(int, input().split()))

from collections import defaultdict

groups = defaultdict(list)

for x in xs:
    r = x % D
    start = x - T * D
    end = x + T * D
    groups[r].append((start, end))

ans = 0

for r in groups:
    intervals = groups[r]
    if not intervals:
        continue
    # Sort intervals by their start value
    intervals.sort()
    merged = []
    current_start, current_end = intervals[0]
    for s, e in intervals[1:]:
        if s <= current_end:
            # Merge the intervals
            current_end = max(current_end, e)
        else:
            merged.append((current_start, current_end))
            current_start, current_end = s, e
    # Add the last merged interval
    merged.append((current_start, current_end))
    # Calculate the number of elements in each merged interval
    for s, e in merged:
        count = (e - s) // D + 1
        ans += count

print(ans)