n = int(input())
ai = input()
# n = 8
# ai = "12 2 34 85 4 91 29 85"
ml = []
def generate_ml():
final = []
for i in ai.split(" "):
final.append(int(i))
return final
ml = generate_ml()
def increase(ai_list, r, l, amount):
for i in range(r, l+1):
ai_list[i] += amount
def broaden(left, right, ai_list):
while (left > 0) and (ai_list[left-1] < ai_list[left]):
left -= 1
while (right < len(ai_list)-1) and (ai_list[right] > ai_list[right+1]):
right += 1
return [left, right]
def focus(ai_list, focus):
total = 0
b = [focus, focus]
b = broaden(b[0], b[1], ml)
while (b != [0, n-1]):
if (b[0] == 0):
left_side = 10**10
else:
left_side = ai_list[b[0]-1] - ai_list[b[0]]
if (b[1] == n-1):
right_side = 10**10
else:
right_side = ai_list[b[1]+1] - ai_list[b[1]]
amount = min(left_side, right_side) + 1
total += amount
increase(ai_list, b[0], b[1], amount)
b = broaden(b[0], b[1], ai_list)
return total
def main():
main_list = generate_ml()
min = focus(main_list, 0)
for i in range(1, n):
main_list = generate_ml()
count = focus(main_list, i)
if count<min:
min = count
print(min)
main()
