A python script to run hackerrank answers on your local. Just run it in the sample test cases folder that you downloaded from hackerrank.

hrtool.py

import re
import glob
import subprocess

from os.path import exists
from sys import exit


INPUT_FOLDER = 'input/'
OUTPUT_FOLDER = 'output/'
SOLUTION_FILE = 'solution.py'

WRONG_PLACE_TO_RUN_MSG = \
    'You have to run this program under, downloaded inputs and outputs.'

REQUIRED_FOLDERS = [INPUT_FOLDER, OUTPUT_FOLDER]
NUMBER_FINDER = re.compile(r'\d+')


def get_output_filename(input_filename):
    return 'output/output%s.txt' % NUMBER_FINDER.findall(input_filename)[0]


wrong_place_to_run = False
for folder in REQUIRED_FOLDERS:
    if not exists(folder):
        print 'Folder \'%s\' does not exists. ' % folder
        wrong_place_to_run = True

if wrong_place_to_run:
    print WRONG_PLACE_TO_RUN_MSG
    exit(1)

if not exists(SOLUTION_FILE):
    print 'Solution must be inside solution.py, put your solution to there ' \
          'and run this command again.'
    exit(1)

input_files = glob.glob('input/*.txt')


for input_file in input_files:
    output_file = get_output_filename(input_file)
    cmd = 'python solution.py'

    process = subprocess.Popen(
        cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE,
        stdin=subprocess.PIPE, shell=True)

    with open(input_file) as f:
        input_data = f.read()

    with open(output_file) as f:
        output_data = f.read()

    out, err = process.communicate(input_data)

    if err:
        print "Error happened when executing your solution:"
        print "--------------------------------------------"
        print err
        exit(1)

    out = out[:-1]
    if out == output_data:
        print '%s: SUCCESS' % input_file
    else:
        print '%s: FAIL' % input_file
    print "-------OUTPUT------"
    print out%