Python - Check if Given String can be Formed by Concatenating String Elements of List Last Updated : 11 Jul, 2025 Comments Improve Suggest changes Like Article Like Report We are given a list of strings we need to check if given string can be formed by concatenating them. For example, a = ["cat", "dog", "bird"] is given list and s = "catdog" is targe string we need to return True or False according to it, so that output should be False in this case.Using a for loopA for loop iterates over each element in the list concatenating them to form a string result is checked against given string to determine if they are equal. Python a = ["cat", "dog", "bird"] s = "catdog" con = "" # Concatenate list elements for element in a: con += element # Check if the concatenated result equals the target res = con == s print(res) OutputFalse Explanation:Code iterates over each element in a appending it to the variable con to form a single string.It checks if the concatenated string matches the target string t returning True or False.Using join.join method concatenates all elements in list into a single string resulting string is then compared to the target string to check for equality. Python a = ["cat", "dog"] s = "catdog" # Join list elements and compare to the target res = "".join(a) == s print(res) OutputTrue Explanation:join method concatenates all elements in list a into a single string without any separator.Concatenated string is compared to target string t returning True if they are equal and False otherwise.Using startswithUsing startswith we check if target string begins with each list element consuming matching part by adjusting the index accordingly. If all elements are matched sequentially and index reaches the target's end string can be formed. Python a = ["cat", "dog"] s = "catdog" # Initialize index and a flag idx = 0 res = True # Iterate through the list and check each word for word in a: # Check if the target substring matches the current word if s[idx:idx + len(word)] == word: idx += len(word) else: result = False break # Check if the entire target was consumed res = res and idx == len(s) print(res) OutputTrue Explanation:Code iterates through each word in list a and checks if the corresponding substring of t matches word.If all words match in sequence and fully consume the target t res is True otherwise it is set to False. Comment More infoAdvertise with us Next Article Interview Preparation For Software Developers S Smitha Dinesh Semwal Follow Improve Article Tags : Python Python Programs Python list-programs Practice Tags : python Similar Reads Interview PreparationInterview Preparation For Software DevelopersMust Coding Questions - Company-wise Must Do Coding Questions - Topic-wiseCompany-wise Practice ProblemsCompany PreparationCompetitive ProgrammingSoftware Design-PatternsCompany-wise Interview ExperienceExperienced - Interview ExperiencesInternship - Interview ExperiencesPractice @GeeksforgeeksProblem of the DayTopic-wise PracticeDifficulty Level - SchoolDifficulty Level - BasicDifficulty Level - EasyDifficulty Level - MediumDifficulty Level - HardLeaderboard !!Explore More...Data StructuresArraysLinked ListStackQueueBinary TreeBinary Search TreeHeapHashingGraphAdvance Data StructuresMatrixStringAll Data StructuresAlgorithmsAnalysis of AlgorithmsSearching AlgorithmsSorting AlgorithmsPattern SearchingGeometric AlgorithmsMathematical AlgorithmsRandomized AlgorithmsGreedy AlgorithmsDynamic ProgrammingDivide & ConquerBacktrackingBranch & BoundAll AlgorithmsProgramming LanguagesCC++JavaPythonC#Go LangSQLPHPScalaPerlKotlinWeb TechnologiesHTMLCSSJavaScriptBootstrapTailwind CSSAngularJSReactJSjQueryNodeJSPHPWeb DesignWeb BrowserFile FormatsComputer Science SubjectsOperating SystemsDBMSComputer NetworkComputer Organization & ArchitectureTOCCompiler DesignDigital Elec. & Logic DesignSoftware EngineeringEngineering MathematicsData Science & MLComplete Data Science CourseData Science TutorialMachine Learning TutorialDeep Learning TutorialNLP TutorialMachine Learning ProjectsData Analysis TutorialTutorial LibraryPython TutorialDjango TutorialPandas TutorialKivy TutorialTkinter TutorialOpenCV TutorialSelenium TutorialGATE CSGATE CS NotesGate CornerPrevious Year GATE PapersLast Minute Notes (LMNs)Important Topic For GATE CSGATE CoursePrevious Year Paper: CS exams Like