Compilare: user.cpp: In function ‘int main()’: user.cpp:67:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("royfloyd.in","r",stdin); ^ user.cpp:68:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("royfloyd.out","w",stdout); ^ user.cpp:74:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &dist[i][j]); ^ user.cpp:70:14: warning: ‘num_values’ may be used uninitialized in this function [-Wmaybe-uninitialized] dist = vector<vector<int>>(num_values, ^