def merge(arr, l, m, r):
    n1 = m - l + 1
    n2 = r - m
    L = []
    R = []
    for i in range(n1):
        L.append(arr[l + i])
    for j in range(n2):
        R.append(arr[m + 1 + j])
    i = 0
    j = 0
    k = l
    while i < n1 and j < n2:
        if L[i][1] < R[j][1] or (L[i][1] == R[j][1] and L[i][0] < R[j][0]):
            arr[k] = L[i]
            i += 1
        else:
            arr[k] = R[j]
            j += 1
        k += 1
    while i < n1:
        arr[k] = L[i]
        i += 1
        k += 1
    while j < n2:
        arr[k] = R[j]
        j += 1
        k += 1


def sort(arr, l, r):
    if l < r:
        m = (l + r) // 2
        sort(arr, l, m)
        sort(arr, m + 1, r)
        merge(arr, l, m, r)


n, x, k = list(map(int, input().split()))
a = list(map(int, input().split()))

brr = []
for el in a:
    b = el % x
    brr.append((el, b))

sort(brr, 0, len(brr) - 1)

lo = 0
hi = pow(10, 18)
while lo < hi:
    mid = (lo + hi) // 2
    col = 0
    last = -1
    for b in brr:
        if b[1] != last and mid >= b[0]:
            col += (mid - b[0]) // x + 1
            last = b[1]
    if k <= col:
        hi = mid
    else:
        lo = mid + 1

print(lo)