Compilare: user.cpp: In function ‘void Print_Answer()’: user.cpp:91:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<answer.size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:112:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<X.size(); i++) ^ user.cpp:113:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j=0; j<Y.size(); j++) ^ user.cpp:121:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<Y.size(); i++) ^ user.cpp:124:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j=0; j<X.size(); j++) ^ user.cpp:136:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<Y.size(); i++) ^ user.cpp:143:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<X.size(); i++) ^ user.cpp:97:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("plan.in", "r", stdin); ^ user.cpp:98:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("plan.out", "w", stdout); ^ user.cpp:99:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &N, &M); ^ user.cpp:103:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &X, &Y); ^