将元素存储在unordered_set中,并将它们存储在unordered_map中

#include<iostream>
#include <unordered_set>
#include <unordered_map>

int main() {
    std::unordered_set<int> set = {1, 2, 3, 4, 5};
    std::unordered_map<int, int> map;

    for (int i : set) {
        map[i] = i * 2;
    }

    for (auto& p : map) {
        std::cout << p.first << " -> " << p.second<< std::endl;
    }

    return 0;
}

1 -> 2
2 -> 4
3 -> 6
4 -> 8
5 -> 10