from sortedcontainers import SortedList
N, K, X = map(int, input().split())
A = list(map(int, input().split()))
sl = SortedList()

ret = []

for i in range(N):
	sl.add(-A[i])
	val = -sum(sl[:min(i+1, K)]) - X * (i+1)
	ret.append(val)
	

print(min(ret))