Suppose we have a list of numbers called nums and another value pos. We have to find a sublist A of nums that includes the index pos such that (minimum of A) * (size of A) is maximized then return the value.
So, if the input is like nums = [-2, 2, 5, 4] pos = 3, then the output will be 8, as the best sublist is [5, 4], because (5, 4) = 4 and its size is 2 we have 4 * 2 = 8.
To solve this, we will follow these steps −
ans := A[pos], m := A[pos]
i := pos, j := pos
do the following for i in range 0 to size of A - 1, do
left := A[i - 1] if i - 1 >= 0 otherwise -inf
right := A[j + 1] if j + 1 < size of A otherwise -inf
if left >= right, then
i := i - 1
m := minimum of m and A[i]
otherwise,
j := j + 1
m := minimum of m and A[j]
ans := maximum of ans and (m *(j - i + 1))
return ans
Example
Let us see the following implementation to get better understanding −
class Solution:
def solve(self, A, pos):
NINF = float("-inf")
ans = m = A[pos]
i = pos
j = pos
for _ in range(len(A) - 1):
left = A[i - 1] if i - 1 >= 0 else NINF
right = A[j + 1] if j + 1 < len(A) else NINF
if left >= right:
i -= 1
m = min(m, A[i])
else:
j += 1
m = min(m, A[j])
ans = max(ans, m * (j - i + 1))
return ans
ob = Solution()
nums = [-2, 2, 5, 4]
pos = 3
print(ob.solve(nums, pos))Input
[-2, 2, 5, 4], 3
Output
8