# Python Program To Check Whether The Given List Is Valley Or Not

Any sequence of integers consisting of strictly decreasing values followed by strictly increasing values such that the decreasing and increasing sequence have a minimum length of 2 and the last value of decreasing sequence is the first value of the increasing sequence is said to be a Valley.

The sequence [ 4, 3. 2, 1, 2, 3, 4] is an example of a Valley. In this article, we will create a Python Program to check wheater the given sequence is a valley or not.

## Python Program To Check Whether The Given List Is Valley Or Not

``````
def valley(l):
if (len(l) < 3):
return False

up_count = 1
low_count = 1

for i in range(0, len(l) - 1):
if l[i] > l[i + 1]:
if low_count > 1:
return False
up_count = up_count + 1
if l[i] < l[i + 1]:
low_count = low_count + 1
if l[i] == l[i + 1]:
return False

if up_count > 1 and low_count > 1:
return True
else:
return False

print(valley([3, 2, 8, 1, 2, 3]))

print(valley([3, 2, 1, 2, 3]))

``````

Output:

````False`
`True````