Compilare: user.cpp: In function ‘void read()’: user.cpp:10:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("3secv.in", "r", stdin); ^ user.cpp:11:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:14:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i]); ^ user.cpp: In function ‘void write()’: user.cpp:118:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] printf("%d %d", bp, ep); ^ user.cpp: In function ‘void solve()’: user.cpp:21:19: warning: ‘a’ may be used uninitialized in this function [-Wmaybe-uninitialized] int p = 1, i, a, b; ^