Compilare: main.cpp: In function 'int main()': main.cpp:46:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < n; ++i) ~~^~~ main.cpp:51:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < m; ++i) ~~^~~ main.cpp:57:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (tmp == -1) ~~~~^~~~~ main.cpp:68:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (tmp == -1) ~~~~^~~~~ main.cpp:85:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (tmp == -1) ~~~~^~~~~