# Python3

splitInput = input().split()
n = int(splitInput[0])
k = int(splitInput[1])

splitInput = input().split()
inputs = []
difNums = []

i = int(0)
while i < n:
    inputs.append(int(splitInput[i]))
    if difNums.count(inputs[i]) == 0:
        difNums.append(inputs[i])
    i += 1

output = int(0)
o = int(0)
p = int(0)

if difNums >= k:
    while o < n:
        while p < n:
            if difNums.count(inputs[p]) == 0:
                difNums.append(inputs[p])
            output += 1
            p += 1
            if len(difNums) > k:
                output -= 1
                difNums.clear()
                p = n
        o += 1
        p = o
        difNums.clear()
else:
    output = n * (n+1) / 2

print(output)