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最大化城市的最小电量（二分+前缀和+差分数组+贪心）
python
class Solution:
def maxPower(self, stations: List[int], r: int, k: int) -> int:
n = len(stations)
sum = list(accumulate(stations, initial=0))
for i in range(n):
stations[i] = sum[min(i + r + 1, n)] - sum[max(i - r, 0)]
def check(target):
diff = [0] * n
sum_d = need = 0
for i, x in enumerate(stations):
sum_d += diff[i]
m = target - x - sum_d
if m > 0:
need += m
if need > k:
return False
sum_d += m
if i + r * 2 + 1 < n:
diff[i + r * 2 + 1] -= m
return True
left = min(stations)
right = left + k
while left < right:
mid = (left + right + 1) // 2
if check(mid):
left = mid
else:
right = mid - 1
return left礼盒的最大甜蜜度（二分）
python
class Solution:
def maximumTastiness(self, price: List[int], k: int) -> int:
n = len(price)
price.sort()
def check(x):
start, cnt = price[0], 1
for i in range(1, n):
if price[i] - start >= x:
cnt += 1
start = price[i]
return cnt >= k
l, r = 0, (price[-1] - price[0]) // (k - 1) + 1
while l < r:
mid = (l + r + 1) >> 1
if check(mid):
l = mid
else:
r = mid - 1
return l