HackerRank Interview Preparation Kit | Warm-up

1. Sales by Match

Solution:

#!/bin/python3

import math
import os
import random
import re
import sys

#
# Complete the 'sockMerchant' function below.
#
# The function is expected to return an INTEGER.
# The function accepts following parameters:
#  1. INTEGER n
#  2. INTEGER_ARRAY ar
#

def sockMerchant(n, ar):
    # Write your code here
    pair =0
    indep_ar = set(ar)
    for i in indep_ar:
        pair += ar.count(i)//2
    return pair

if __name__ == '__main__':
    fptr = open(os.environ['OUTPUT_PATH'], 'w')

    n = int(input().strip())

    ar = list(map(int, input().rstrip().split()))

    result = sockMerchant(n, ar)

    fptr.write(str(result) + '\n')

    fptr.close()

점프 투 파이썬

2. Counting Valleys

Solution:

#!/bin/python3

import math
import os
import random
import re
import sys

#
# Complete the 'countingValleys' function below.
#
# The function is expected to return an INTEGER.
# The function accepts following parameters:
#  1. INTEGER steps
#  2. STRING path
#

def countingValleys(steps, path):
    # Write your code here
    valley = 0
    seaL = 0
    for i in range (0,steps):
        if (path[i] == 'U'):
            seaL += 1
        elif (path[i] == 'D'):
            seaL -= 1
        if (seaL == 0 and path[i] == 'U'):
            valley += 1
    return (valley)

if __name__ == '__main__':
    fptr = open(os.environ['OUTPUT_PATH'], 'w')

    steps = int(input().strip())

    path = input()

    result = countingValleys(steps, path)

    fptr.write(str(result) + '\n')

    fptr.close()

3. Jumping on the Clouds

Solution:

#!/bin/python3

import math
import os
import random
import re
import sys

#
# Complete the 'jumpingOnClouds' function below.
#
# The function is expected to return an INTEGER.
# The function accepts INTEGER_ARRAY c as parameter.
#

def jumpingOnClouds(c):
    # Write your code here
    jump=0
    start=0
    while start<len(c):
        if start+2<len(c) and c[start+2]==0:
            start+=2
            jump+=1
        else:
            start+=1
            jump+=1
    return jump-1

if __name__ == '__main__':
    fptr = open(os.environ['OUTPUT_PATH'], 'w')

    n = int(input().strip())

    c = list(map(int, input().rstrip().split()))

    result = jumpingOnClouds(c)

    fptr.write(str(result) + '\n')

    fptr.close()

4. Repeated String

Solution:

#!/bin/python3

import math
import os
import random
import re
import sys

#
# Complete the 'repeatedString' function below.
#
# The function is expected to return a LONG_INTEGER.
# The function accepts following parameters:
#  1. STRING s
#  2. LONG_INTEGER n
#

def repeatedString(s, n):
    # Write your code here
    return s.count('a') * int(n / len(s)) + s[:n % len(s)].count('a')


if __name__ == '__main__':
    fptr = open(os.environ['OUTPUT_PATH'], 'w')

    s = input()

    n = int(input().strip())

    result = repeatedString(s, n)

    fptr.write(str(result) + '\n')

    fptr.close()