N,T=list(map(int,input().split()))

t=list(map(int,input().split()))

a=T

for i in range(N-1):

  a+=min(T,t[i+1]-t[i])

print(a)
N,T=list(map(int,input().split()))

t=list(map(int,input().split()))

a=[min(T,t[i+1]-t[i]) for i in range(N-1)]

print((sum(a)+T))
N, T = list(map(int, input().split()))
t = list(map(int, input().split()))
a = T
for i in range(N - 1):
    a += min(T, t[i + 1] - t[i])
print(a)

N, T = list(map(int, input().split()))
t = list(map(int, input().split()))
a = [min(T, t[i + 1] - t[i]) for i in range(N - 1)]
print((sum(a) + T))

-a = T -for i in range(N - 1): -    a += min(T, t[i + 1] - t[i]) -print(a) +a = [min(T, t[i + 1] - t[i]) for i in range(N - 1)] +print((sum(a) + T))