Compilare: main.cpp: In function 'elem calcVal(elem, elem, char)': main.cpp:15:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i < X.size() && j < Y.size()) ~~^~~~~~~~~~ main.cpp:15:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i < X.size() && j < Y.size()) ~~^~~~~~~~~~ main.cpp:19:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i < X.size()) TORET.push_back(X[i++]); ~~^~~~~~~~~~ main.cpp:20:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j < Y.size()) TORET.push_back(Y[j++]); ~~^~~~~~~~~~ main.cpp:23:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i < X.size() && j < Y.size()) ~~^~~~~~~~~~ main.cpp:23:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i < X.size() && j < Y.size()) ~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:68:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i < crt.length(); ++i) ~~^~~~~~~~~~~~~~ main.cpp:71:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i < crt.length() && isdigit(crt[i])) ~~^~~~~~~~~~~~~~ main.cpp:61:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("multimi4.in", "r", stdin); ^ main.cpp:62:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("multimi4.out", "w", stdout); ^