Compilare: user.cpp: In function ‘int main()’: user.cpp:30:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("proc2.in", "r", stdin); ^ user.cpp:31:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("proc2.out", "w", stdout); ^ user.cpp:32:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n", &n, &m); ^ user.cpp:37:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n", &v[i].b, &v[i].e); ^