unordered_multimap find() function in C++ STL Last Updated : 23 Feb, 2023 Comments Improve Suggest changes Like Article Like Report The unordered_multimap::find() is a built-in function in C++ STL which returns an iterator which points to one of the elements which has the key k. If the container does not contain any element with key k, then it returns an iterator which points to the position which is past the last element in the container. Syntax: unordered_multimap_name.find(k) Parameters: The function accepts a mandatory parameter k which specifies the key. Return Value: It returns an iterator which points to the position where an element with key k is. Below programs illustrate the above function: Program 1: CPP // C++ program to illustrate the // unordered_multimap::find() function #include <iostream> #include <unordered_map> using namespace std; int main() { // declaration unordered_multimap<int, int> sample; // inserts key and element sample.insert({ 1, 2 }); sample.insert({ 1, 2 }); sample.insert({ 2, 3 }); sample.insert({ 3, 4 }); sample.insert({ 2, 6 }); // find the element with key 1 and print auto it = sample.find(1); if (it != sample.end()) cout << 1 << ":" << it->second << endl; else cout << "element with key 1 not found\n"; // find the element with // key 2 and print it = sample.find(2); if (it != sample.end()) cout << 2 << ":" << it->second << endl; else cout << "element with key 2 not found\n"; // find the element with // key 100 and print it = sample.find(100); if (it != sample.end()) cout << 100 << ":" << it->second << endl; else cout << "element with key 100 not found\n"; return 0; } Output:1:2 2:6 element with key 100 not found Program 2: CPP // C++ program to illustrate the // unordered_multimap::find() #include <iostream> #include <unordered_map> using namespace std; int main() { // declaration unordered_multimap<char, char> sample; // inserts element sample.insert({ 'a', 'b' }); sample.insert({ 'a', 'b' }); sample.insert({ 'a', 'd' }); sample.insert({ 'b', 'e' }); sample.insert({ 'b', 'd' }); // find the element with // key r and print auto it = sample.find('r'); if (it != sample.end()) cout << "r" << ":" << it->second << endl; else cout << "element with key or not found\n"; // find the element with // key a and print it = sample.find('a'); if (it != sample.end()) cout << 'a' << ":" << it->second << endl; else cout << "element with key a not found\n"; // find the element with // key 'b' and print it = sample.find('b'); if (it != sample.end()) cout << "b" << ":" << it->second << endl; else cout << "element with key b not found\n"; return 0; } Output:element with key r not found a:d b:d Comment More infoAdvertise with us Next Article unordered_multimap count() function in C++ STL G gopaldave Follow Improve Article Tags : Misc C++ STL CPP-Functions cpp-unordered_multimap +1 More Practice Tags : CPPMiscSTL Similar Reads Unordered Multimap in C++ STL In C++, the unordered_multimap is an unordered associative container that stores data in the form of key-value pairs. 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