Compilare: main.cpp: In function 'bool expresie()': main.cpp:21:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (poz < linie.size() - 3 && linie[poz] == ' ' && linie[poz + 1] == 'O' && linie[poz + 2] == 'R' && linie[poz + 3] == ' ') ~~~~^~~~~~~~~~~~~~~~~~ main.cpp: In function 'bool sau()': main.cpp:34:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (poz < linie.size() - 4 && linie[poz] == ' ' && linie[poz + 1] == 'A' && linie[poz + 2] == 'N' && linie[poz + 3] == 'D' && linie[poz + 4] == ' ') ~~~~^~~~~~~~~~~~~~~~~~ main.cpp: In function 'bool paranteze()': main.cpp:54:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (poz < linie.size() - 1 && linie[poz] == '(') ~~~~^~~~~~~~~~~~~~~~~~ main.cpp:62:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] else if (poz < linie.size() - 3 && linie[poz] == 'N' && linie[poz + 1] == 'O' && linie[poz + 2] == 'T' && linie[poz + 3] == ' ') ~~~~^~~~~~~~~~~~~~~~~~ main.cpp:68:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] else if (poz < linie.size() - 3 && linie[poz] == 'T' && linie[poz + 1] == 'R' && linie[poz + 2] == 'U' && linie[poz + 3] == 'E') ~~~~^~~~~~~~~~~~~~~~~~ main.cpp:74:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] else if (poz < linie.size() - 4 && linie[poz] == 'F' && linie[poz + 1] == 'A' && linie[poz + 2] == 'L' && linie[poz + 3] == 'S' && linie[poz + 4] == 'E') ~~~~^~~~~~~~~~~~~~~~~~ main.cpp:80:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] else if (poz < linie.size()) ~~~~^~~~~~~~~~~~~~ main.cpp:87:12: warning: 'sol' may be used uninitialized in this function [-Wmaybe-uninitialized] return sol; ^~~