Compilare: user.cpp: In function ‘int main()’: user.cpp:4:22: warning: integer overflow in expression [-Woverflow] #define inf ((2<<30)-1) ^ user.cpp:34:31: note: in expansion of macro ‘inf’ G[i][j] = inf; ^ user.cpp:4:22: warning: integer overflow in expression [-Woverflow] #define inf ((2<<30)-1) ^ user.cpp:40:35: note: in expansion of macro ‘inf’ if(G[i][k] != inf && G[k][j] != inf) ^ user.cpp:4:22: warning: integer overflow in expression [-Woverflow] #define inf ((2<<30)-1) ^ user.cpp:40:53: note: in expansion of macro ‘inf’ if(G[i][k] != inf && G[k][j] != inf) ^ user.cpp:4:22: warning: integer overflow in expression [-Woverflow] #define inf ((2<<30)-1) ^ user.cpp:46:31: note: in expansion of macro ‘inf’ if(G[i][j] != inf) ^ user.cpp:13:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rfinv.in", "rt", stdin); ^ user.cpp:14:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rfinv.out", "wt", stdout); ^ user.cpp:15:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &T); ^ user.cpp:19:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &N, &M); ^ user.cpp:25:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a, &b); ^ user.cpp:30:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &C[i][j]); ^