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contains for Associative Containers

contains for Associative Containers

Understand the details of the 'contains' function.

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Thanks to the function contains, you can easily check if an element exists in an associative container. Stop, you may say, we can already do this with find or count. No, both functions are not beginner-friendly and have their downsides.

Erasing elements from a container

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#include <set>
#include <iostream>
int main() {
    std::cout << '\n';
    std::set mySet{3, 2, 1};
    if (mySet.find(2) != mySet.end()) {
        std::cout << "2 inside" << '\n';
    }
    std::multiset myMultiSet{3, 2, 1, 2};
    if (myMultiSet.count(2)) {
        std::cout << "2 inside" << '\n';
    }
    std::cout << '\n';
}

There are issues with both calls. The find call (line 8) ...