Compilare: user.cpp: In function ‘int main()’: user.cpp:25:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("campion.in", "r", stdin); ^ user.cpp:26:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("campion.out", "w", stdout); ^ user.cpp:28:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &t); ^ user.cpp:30:53: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lld%d", &elev[i].rate, &elev[i].add); ^ user.cpp:42:9: warning: ‘prec’ may be used uninitialized in this function [-Wmaybe-uninitialized] if(stak[1] != prec){ ^