1 5 D 7

def input_read():
    n, r = [int(x) for x in input().split()]
    monuments = [int(x) for x in input().split()]
    return n, r, monuments


def monuments_count(n, r, monuments):
    count = 0
    left = 0
    right = 1
    while True:
        while right + 1 < n and monuments[right] - monuments[left] <= r:
            right += 1
        if monuments[right] - monuments[left - 1] > r:
            count += left
        while left < right and monuments[right] - monuments[left] > r:
            left += 1
            count += 1
        if right + 1 >= n:
            break
    return count


def main():
    print(monuments_count(*input_read()))


if __name__ == '__main__':
    main()