Compilare: main.cpp: In function 'std::vector<int> reunion(std::vector<int>&, std::vector<int>&)': main.cpp:19:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < a.size() && j < b.size()) { ~~^~~~~~~~~~ main.cpp:19:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < a.size() && j < b.size()) { ~~^~~~~~~~~~ main.cpp:35:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < a.size()) { ~~^~~~~~~~~~ main.cpp:40:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (j < b.size()) { ~~^~~~~~~~~~ main.cpp: In function 'std::vector<int> intersection(std::vector<int>&, std::vector<int>&)': main.cpp:53:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < a.size() && j < b.size()) { ~~^~~~~~~~~~ main.cpp:53:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < a.size() && j < b.size()) { ~~^~~~~~~~~~ main.cpp: In function 'std::vector<int> eval()': main.cpp:72:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (; pos < eq.size(); ++pos) { ~~~~^~~~~~~~~~~ main.cpp:90:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < ans.size(); ++i) ~~^~~~~~~~~~~~ main.cpp:108:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < ans.size(); ++i) ~~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:139:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (; j < line.size(); ++j) ~~^~~~~~~~~~~~~