finished

.gitignore

@@ -0,0 +1,4 @@
+*__cache__*
+*__pycache__*
+.venv
+.pytest_cache

README.md

@@ -0,0 +1,43 @@
+# Nordhealth test
+
+## Problem
+
+Given an unsorted array A[]. The task is to print all unique pairs in the unsorted array with equal sum.
+Note: Print the result in the format as shown in the below examples.
+
+Examples:
+```
+Input: A[] = { 6, 4, 12, 10, 22, 54, 32, 42, 21, 11}
+Output:
+Pairs : ( 4, 12) ( 6, 10) have sum : 16
+Pairs : ( 10, 22) ( 21, 11) have sum : 32
+Pairs : ( 12, 21) ( 22, 11) have sum : 33
+Pairs : ( 22, 21) ( 32, 11) have sum : 43
+Pairs : ( 32, 21) ( 42, 11) have sum : 53
+Pairs : ( 12, 42) ( 22, 32) have sum : 54
+Pairs : ( 10, 54) ( 22, 42) have sum : 64
+```
+```
+Input:A[]= { 4, 23, 65, 67, 24, 12, 86}
+Output:
+Pairs : ( 4, 86) ( 23, 67) have sum : 90
+```
+
+## Solution
+
+Solution in `nordhealth_test/solution.py:51` (print_pairs_with_same_sum())
+
+Tests for the inputs are defined it `tests/test_solution.py`
+
+For package manager I am using poetry, so to activate venv:
+ - `poetry install`
+ - `poetry env activate`
+
+## Running 
+to run the solution:
+ - `chmod +x ./nordhealth_test/solution.py`
+ - `./nordhealth_test/solution.py [path to input file]`
+     - Example: `./nordhealth_test/solution.py ./inputs/input1.txt`
+
+To run the tests:
+ - `pytest tests/`

inputs/input1.txt

@@ -0,0 +1 @@
+6,4,12,10,22,54,32,42,21,11

inputs/input2.txt

@@ -0,0 +1 @@
+4,23,65,67,24,12,86

nordhealth_test/solution.py

@@ -0,0 +1,98 @@
+#!/usr/bin/env python3
+import sys
+from typing import List
+from collections import defaultdict
+
+"""
+Given an unsorted array A[]. The task is to print all unique pairs in the unsorted array with equal sum.
+Note: Print the result in the format as shown in the below examples.
+
+Examples:
+
+Input: A[] = { 6, 4, 12, 10, 22, 54, 32, 42, 21, 11}
+Output:
+Pairs : ( 4, 12) ( 6, 10) have sum : 16
+Pairs : ( 10, 22) ( 21, 11) have sum : 32
+Pairs : ( 12, 21) ( 22, 11) have sum : 33
+Pairs : ( 22, 21) ( 32, 11) have sum : 43
+Pairs : ( 32, 21) ( 42, 11) have sum : 53
+Pairs : ( 12, 42) ( 22, 32) have sum : 54
+Pairs : ( 10, 54) ( 22, 42) have sum : 64
+
+Input:A[]= { 4, 23, 65, 67, 24, 12, 86}
+Output:
+Pairs : ( 4, 86) ( 23, 67) have sum : 90
+"""
+def main() -> None:
+    argc = len(sys.argv)
+    argv = sys.argv
+    if argc != 2:
+        raise ValueError("Invalid input. You need to provide a single path to the input file. \n Ex.: `./solution.py ./input1.txt`")
+    
+    # Read input from the file and process the data
+    try:
+        input_data = read_input(argv[1])
+        print_pairs_with_same_sum(input_data)
+    except ValueError as e:
+        print(f"Error: {e}")
+        sys.exit(1)
+    
+
+def read_input(input_file: str) -> List[int]:
+    """ Reads the input file and returns a list of integers. """
+    try:
+        with open(input_file, "r") as file:
+            lst = file.readline().split(',')
+            parsed = [int(x.strip()) for x in lst]
+            return parsed
+    except Exception as e:
+        raise ValueError(f"Failed to read or parse the file: {e}")
+
+def print_pairs_with_same_sum(arr: List[int]) -> None:
+    """
+    Solution to the problem. Since performance is required it's in one method, but could be separated:
+    1). Calculate the sums into a hashmap and add the pairs
+    2). print the result
+    """
+    
+    # Not a valid array
+    if len(arr) < 2:
+        print("No pairs can be formed from the input file.")
+
+    sum_map = defaultdict(list)
+    
+    # Check for duplicate pairs. 
+    seen_pairs = set()
+
+    n = len(arr)
+    
+    for i in range(n):
+        # Time Complexity (O(n^2)), as we have n(n-1)/2 for the second loop.
+        for j in range(i + 1, n):
+            current_sum = arr[i] + arr[j]
+            pair = tuple((arr[i], arr[j]))
+
+            if pair not in seen_pairs:
+                # This will output nothing for [2,2,2,2]. Depending on the requirements we can store the pair using indices,
+                # then the result would be: 
+                # (A[0],A[1]) (A[0],A[2]) (A[0],A[3]) (A[1],A[2]) (A[1],A[3]) (A[2],A[3]) - sum: 4
+                # And we will not need the seen_pairs set.
+                sum_map[current_sum].append(pair)
+                seen_pairs.add(pair)
+    
+    # This is required to follow the example output, as it is presented as sorted by sum in the task description. 
+    # We can skip the sorting if this is not really part of the requiremetns.
+    for sum_val in sorted(sum_map.keys()):
+        pairs = sum_map[sum_val]
+        
+        if len(pairs) > 1:
+            pairs.sort()
+
+            print(f"Pairs : ", end="")
+            for pair in pairs:
+                print(f"( {pair[0]}, {pair[1]})", end=" ")
+            print(f"have sum : {sum_val}")
+
+
+if __name__ == "__main__":
+    main()

poetry.lock

@@ -0,0 +1,80 @@
+# This file is automatically @generated by Poetry 2.1.1 and should not be changed by hand.
+
+[[package]]
+name = "colorama"
+version = "0.4.6"
+description = "Cross-platform colored terminal text."
+optional = false
+python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*,!=3.5.*,!=3.6.*,>=2.7"
+groups = ["dev"]
+markers = "sys_platform == \"win32\""
+files = [
+    {file = "colorama-0.4.6-py2.py3-none-any.whl", hash = "sha256:4f1d9991f5acc0ca119f9d443620b77f9d6b33703e51011c16baf57afb285fc6"},
+    {file = "colorama-0.4.6.tar.gz", hash = "sha256:08695f5cb7ed6e0531a20572697297273c47b8cae5a63ffc6d6ed5c201be6e44"},
+]
+
+[[package]]
+name = "iniconfig"
+version = "2.1.0"
+description = "brain-dead simple config-ini parsing"
+optional = false
+python-versions = ">=3.8"
+groups = ["dev"]
+files = [
+    {file = "iniconfig-2.1.0-py3-none-any.whl", hash = "sha256:9deba5723312380e77435581c6bf4935c94cbfab9b1ed33ef8d238ea168eb760"},
+    {file = "iniconfig-2.1.0.tar.gz", hash = "sha256:3abbd2e30b36733fee78f9c7f7308f2d0050e88f0087fd25c2645f63c773e1c7"},
+]
+
+[[package]]
+name = "packaging"
+version = "24.2"
+description = "Core utilities for Python packages"
+optional = false
+python-versions = ">=3.8"
+groups = ["dev"]
+files = [
+    {file = "packaging-24.2-py3-none-any.whl", hash = "sha256:09abb1bccd265c01f4a3aa3f7a7db064b36514d2cba19a2f694fe6150451a759"},
+    {file = "packaging-24.2.tar.gz", hash = "sha256:c228a6dc5e932d346bc5739379109d49e8853dd8223571c7c5b55260edc0b97f"},
+]
+
+[[package]]
+name = "pluggy"
+version = "1.5.0"
+description = "plugin and hook calling mechanisms for python"
+optional = false
+python-versions = ">=3.8"
+groups = ["dev"]
+files = [
+    {file = "pluggy-1.5.0-py3-none-any.whl", hash = "sha256:44e1ad92c8ca002de6377e165f3e0f1be63266ab4d554740532335b9d75ea669"},
+    {file = "pluggy-1.5.0.tar.gz", hash = "sha256:2cffa88e94fdc978c4c574f15f9e59b7f4201d439195c3715ca9e2486f1d0cf1"},
+]
+
+[package.extras]
+dev = ["pre-commit", "tox"]
+testing = ["pytest", "pytest-benchmark"]
+
+[[package]]
+name = "pytest"
+version = "8.3.5"
+description = "pytest: simple powerful testing with Python"
+optional = false
+python-versions = ">=3.8"
+groups = ["dev"]
+files = [
+    {file = "pytest-8.3.5-py3-none-any.whl", hash = "sha256:c69214aa47deac29fad6c2a4f590b9c4a9fdb16a403176fe154b79c0b4d4d820"},
+    {file = "pytest-8.3.5.tar.gz", hash = "sha256:f4efe70cc14e511565ac476b57c279e12a855b11f48f212af1080ef2263d3845"},
+]
+
+[package.dependencies]
+colorama = {version = "*", markers = "sys_platform == \"win32\""}
+iniconfig = "*"
+packaging = "*"
+pluggy = ">=1.5,<2"
+
+[package.extras]
+dev = ["argcomplete", "attrs (>=19.2)", "hypothesis (>=3.56)", "mock", "pygments (>=2.7.2)", "requests", "setuptools", "xmlschema"]
+
+[metadata]
+lock-version = "2.1"
+python-versions = ">=3.13"
+content-hash = "8ef1d528c82ebf4a734833eed980b6b031e288bf5563655b512f75969b90d60a"

pyproject.toml

@@ -0,0 +1,20 @@
+[project]
+name = "nordhealth-test"
+version = "0.1.0"
+description = ""
+authors = [
+    {name = "viktor",email = "me@vpanteleev.com"}
+]
+readme = "README.md"
+requires-python = ">=3.13"
+dependencies = [
+]
+
+[tool.poetry]
+
+[tool.poetry.group.dev.dependencies]
+pytest = "^8.3.5"
+
+[build-system]
+requires = ["poetry-core>=2.0.0,<3.0.0"]
+build-backend = "poetry.core.masonry.api"

tests/test_solution.py

@@ -0,0 +1,55 @@
+import sys
+from io import StringIO
+from nordhealth_test.solution import print_pairs_with_same_sum
+
+def capture_output(func, *args, **kwargs):
+    captured_output = StringIO()
+    sys.stdout = captured_output
+    func(*args, **kwargs)
+    sys.stdout = sys.__stdout__
+    return captured_output.getvalue()
+
+# Test case Input 1: [6, 4, 12, 10, 22, 54, 32, 42, 21, 11]
+def test_input_1():
+    arr = [6, 4, 12, 10, 22, 54, 32, 42, 21, 11]
+    expected_output = (
+        "Pairs : ( 4, 12) ( 6, 10) have sum : 16\n"
+        "Pairs : ( 10, 22) ( 21, 11) have sum : 32\n"
+        "Pairs : ( 12, 21) ( 22, 11) have sum : 33\n"
+        "Pairs : ( 22, 21) ( 32, 11) have sum : 43\n"
+        "Pairs : ( 32, 21) ( 42, 11) have sum : 53\n"
+        "Pairs : ( 12, 42) ( 22, 32) have sum : 54\n"
+        "Pairs : ( 10, 54) ( 22, 42) have sum : 64\n"
+    )
+    result = capture_output(print_pairs_with_same_sum, arr)
+    assert result == expected_output
+
+# Test case Input 2: [4, 23, 65, 67, 24, 12, 86]
+def test_input_2():
+    arr = [4, 23, 65, 67, 24, 12, 86]
+    expected_output = (
+        "Pairs : ( 4, 86) ( 23, 67) have sum : 90\n"
+    )
+    result = capture_output(print_pairs_with_same_sum, arr)
+    assert result == expected_output
+
+# Test case: Array with no valid pairs
+def test_no_valid_pairs():
+    arr = [1, 2, 3, 5]
+    expected_output = ""
+    result = capture_output(print_pairs_with_same_sum, arr)
+    assert result == expected_output
+
+# Test case: Array with exactly one element
+def test_single_element():
+    arr = [10]
+    expected_output = "No pairs can be formed from the input file.\n"
+    result = capture_output(print_pairs_with_same_sum, arr)
+    assert result == expected_output
+
+# Test case: Empty array
+def test_empty_array():
+    arr = []
+    expected_output = "No pairs can be formed from the input file.\n"
+    result = capture_output(print_pairs_with_same_sum, arr)
+    assert result == expected_output