Compilare: user.cpp: In function ‘int main()’: user.cpp:69:11: warning: unknown escape sequence: '\m' [enabled by default] scanf("%d %d %d %d\m", &n, &m, &start, &stop); ^ user.cpp:66:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("graf.in" ,"r", stdin); ^ user.cpp:67:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("graf.out" ,"w", stdout); ^ user.cpp:69:50: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d\m", &n, &m, &start, &stop); ^ user.cpp:74:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n", &x, &y); ^