4 monke

lian = int(input())
d = int(input())
jumps = []
for i in range(lian):
    jumps.append(int(input()))
i = 0
while i < (lian - 1):
    if jumps[i] // d == 0:
        break
    max_jump = jumps[i] // d
    for j in range(i + 1, i + jumps[i] // d + 1):
        if j >= lian - 1:
            break
        if jumps[j] // d + j - i > max_jump:
            max_jump = jumps[j] // d + j - i
    i += max_jump
    if i >= lian - 1:
        i = lian - 1
        break
print(i + 1)