[Python] A program that counts the number of valleys

[Python] A program that counts the number of valleys

▼ Question

--Start from 0 height --If it is U, it is on 1. If it is D, it goes down by 1. ――The end will always be at a height of 0. --Calculate the number of valleys from the start to the end.


▼sample input



▼sample output



Image of the road

_/\      _
   \    /

▼my answer


def countingValleys(n, s):
    #U and D as 1-Convert to 1
    ss = list(map(int, (s.replace("U","1 ").replace("D","-1 ").split())))

    #Condition to become a valley (0->-Find the number of occurrences of 1)
    for i in ss:
        if x==0 and x+i < 0:
        x += i
    return ans

if __name__ == '__main__':
    fptr = open(os.environ['OUTPUT_PATH'], 'w')
    n = int(input())
    s = input()
    result = countingValleys(n, s)
    fptr.write(str(result) + '\n')

・ Avid hiker avid: enthusiastic hiker: hiker

・ Emeticulously Pay close attention He tracks his hikes meticulously. A detailed record of hikes.

・ Topography terrain Paying close attention to small details like topography.

## Make the for statement one sentence.

▼ my answer (if is a culture)


def countingValleys(n, s):
    #U and D as 1-Convert to 1
    ss = list(map(int, (s.replace("U","1 ").replace("D","-1 ").split())))

    #Write if in one sentence
    x = ans=0
    for i in ss:
        ans += 1 if x==0 and x+i < 0 else 0
        x += i
    return ans

[Expression for True] if [Condition] else [Expression for False]

For further simplification, I tried to use the comprehension notation, but I didn't know how to write the comprehension notation when there are multiple expressions in the for statement.

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