n, k, x = map(int, input().split())
a = list(map(int, input().split()))

score = -x

for i in range(1, n+1):
	scoref = []

	
	ba = a[:i]
	ba.sort(reverse = True)
	
	for j in range(min(k, i)):
		scoref.append(ba[j])

	curr_score = sum(scoref) - x*i
	
	score = max(curr_score, score)
print(score)