Compilare: user.cpp: In function ‘void dfstd(int, int)’: user.cpp:81:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < mov[x].size(); ++i) { ^ user.cpp: In function ‘int main()’: user.cpp:92:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("optic.in", "r", stdin); ^ user.cpp:93:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("optic.out", "w", stdout); ^ user.cpp:96:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:100:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); --x; --y; ^