Compilare: main.cpp: In function 'int main()': main.cpp:49:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("secv3.in","r",stdin); ^ main.cpp:50:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("secv3.out","w",stdout); ^ main.cpp:51:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &n, &l, &u); ^ main.cpp:53:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i]); ^ main.cpp:56:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t[i]); ^ main.cpp: In function 'double cb()': main.cpp:45:12: warning: 'last' may be used uninitialized in this function [-Wmaybe-uninitialized] return last; ^~~~