Compilare: user.cpp: In function ‘int main()’: user.cpp:54:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k=0; k<A.size(); k++) ^ user.cpp:64:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k=0; k<A.size(); k++) ^ user.cpp:25:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arhipelag.in", "r", stdin); ^ user.cpp:26:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("arhipelag.out", "w", stdout); ^ user.cpp:27:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &N, &M); ^ user.cpp:30:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i][j]); ^