Compilare: user.cpp: In function ‘int main()’: user.cpp:147:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("heavypath.in", "r", stdin); ^ user.cpp:148:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("heavypath.out", "w", stdout); ^ user.cpp:157:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a, &b); ^ user.cpp:177:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a); ^ user.cpp:178:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &c, &d); ^ user.cpp: In function ‘void calch(int, int, int, int)’: user.cpp:109:42: warning: ‘elmax’ may be used uninitialized in this function [-Wmaybe-uninitialized] calch(*it, nod, la, pozz + 1); ^