Compilare: user.cpp: In function ‘void read()’: user.cpp:30:15: warning: unused variable ‘D’ [-Wunused-variable] int i, j, D; ^ user.cpp: In function ‘void Dijkstra()’: user.cpp:48:9: warning: unused variable ‘i’ [-Wunused-variable] int i, D; ^ user.cpp: In function ‘void read()’: user.cpp:31:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("volum.in", "r", stdin); ^ user.cpp:32:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ user.cpp:36:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i][j]); ^ user.cpp: In function ‘void write()’: user.cpp:92:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("volum.out", "w", stdout); ^