# Problem with "Number List" problem from HackerRank

I’m trying to solve the Number List problem from HackerRank

Here’s what I did at first, but I was getting the error “time limit exceeded”:

``````def solve(a, k):
N = len(a)
# s_max contains the max elements of each contiguous subarray
s_max=[max(a[i:i+j]) for i in range(0,N) for j in range(1,N-i+1)]
s_max.sort()

l = 0
r = len(s_max)-1
while True:
mid = (r+l)//2
if mid == l:
return len(s_max)-r
elif s_max[mid] <= k:
l = mid
else:
r = mid
``````

The double for loop thing while creating `s_max` was probably the problem here. For large lists `a` , this would take a lot of time.

The next thing I tried was this: for each number ‘n’ in array `a` , if it’s larger than k, find out in how many subarrays it is the maximum. It can be done by counting elements to the left of ‘n’ till I get something larger, and then doing the same thing on the right. Then the number of such subarrays where n>k and ‘n’ is the max = product of those two ‘left’ and ‘right’ numbers. This is my code:

``````def solve(a, k):
N = len(a)
if max(a) < k:  # no subarray will have a max > k
return 0
if k < min(a):  # all subarrays will have max > k
return N*(N+1)//2
cnt = 0
for ind, val in enumerate(a):
if val > k:
# count subarrays where val > k and val=max(subarray)
# and val is the rightmost element
j = ind-1
left = 1
while j >= 0 and a[j] <= val:
left += 1
j -= 1

# count subarrays where val > k and val=max(subarray)
# and val is the leftmost element
right = 1
j = ind+1
while j < N and a[j] <= val:
right += 1
j += 1

# total subarrays with max(subarray) > k
cnt += left * right
return cnt
``````

This did solve the problem of “time limit exceeded”, but in two test cases, I’m getting the error “Wrong Answer”. What am I doing wrong here?