list size() function in C++ STL Last Updated : 02 Dec, 2022 Comments Improve Suggest changes Like Article Like Report The list::size() is a built-in function in C++ STL that is used to find the number of elements present in a list container. That is, it is used to find the size of the list container.Syntax: list_name.size(); Time Complexity - Linear O(1) as per c++11 standard. Possible because the implementation maintains the size field. Parameters: This function does not accept any parameter.Return Value: This function returns the number of elements present in the list container list_name. Below program illustrate the list::size() function in C++ STL: CPP // CPP program to illustrate the // list::size() function #include <bits/stdc++.h> using namespace std; int main() { // Creating a list list<int> demoList; // Add elements to the List demoList.push_back(10); demoList.push_back(20); demoList.push_back(30); demoList.push_back(40); // getting size of the list int size = demoList.size(); cout << "The list contains " << size << " elements"; return 0; } Comment More infoAdvertise with us B barykrg Follow Improve Article Tags : Misc C++ STL CPP-Functions cpp-list +1 More Practice Tags : CPPMiscSTL Explore C++ Programming Language 5 min read C++ OverviewIntroduction to C++ Programming Language 3 min read Features of C++ 5 min read History of C++ 7 min read Interesting Facts about C++ 2 min read Setting up C++ Development Environment 8 min read Difference between C and C++ 3 min read C++ BasicsUnderstanding First C++ Program 4 min read C++ Basic Syntax 4 min read C++ Comments 3 min read Tokens in C 4 min read C++ Keywords 2 min read Difference between Keyword and Identifier in C 3 min read C++ Variables and ConstantsC++ Variables 4 min read Constants in C 4 min read Scope of Variables in C++ 7 min read Storage Classes in C++ with Examples 6 min read Static Keyword in C++ 5 min read C++ Data Types and LiteralsC++ Data Types 7 min read Literals in C 4 min read Derived Data Types in C++ 4 min read User Defined Data Types in C++ 4 min read Data Type Ranges and Their Macros in C++ 3 min read C++ Type Modifiers 4 min read Type Conversion in C++ 4 min read Casting Operators in C++ 5 min read C++ OperatorsOperators in C++ 9 min read C++ Arithmetic Operators 4 min read Unary Operators in C 5 min read Bitwise Operators in C 6 min read Assignment Operators in C 4 min read C++ sizeof Operator 3 min read Scope Resolution Operator in C++ 4 min read C++ Input/OutputBasic Input / Output in C++ 5 min read cin in C++ 4 min read cout in C++ 2 min read Standard Error Stream Object - cerr in C++ 2 min read Manipulators in C++ 4 min read C++ Control StatementsDecision Making in C (if , if..else, Nested if, if-else-if ) 7 min read C++ if Statement 3 min read C++ if else Statement 3 min read C++ if else if Ladder 3 min read Switch Statement in C++ 5 min read Jump statements in C++ 4 min read C++ Loops 7 min read for Loop in C++ 6 min read Range-Based for Loop in C++ 3 min read C++ While Loop 3 min read C++ do while Loop 4 min read C++ FunctionsFunctions in C++ 8 min read return Statement in C++ 4 min read Parameter Passing Techniques in C 3 min read Difference Between Call by Value and Call by Reference in C 4 min read Default Arguments in C++ 5 min read Inline Functions in C++ 6 min read Lambda Expression in C++ 4 min read C++ Pointers and ReferencesPointers and References in C++ 5 min read C++ Pointers 8 min read Dangling, Void , Null and Wild Pointers in C 6 min read Applications of Pointers in C 4 min read Understanding nullptr in C++ 3 min read References in C++ 5 min read Can References Refer to Invalid Location in C++? 2 min read Pointers vs References in C++ 5 min read Passing By Pointer vs Passing By Reference in C++ 5 min read When do we pass arguments by pointer? 5 min read Like