Compilare: user.cpp: In function ‘int main()’: user.cpp:127:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("invsort.in", "r", stdin); ^ user.cpp:128:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("invsort.out", "w", stdout); ^ user.cpp:129:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:130:50: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i = 1; i<= n; ++i) scanf("%d", &v[i]); ^ user.cpp: In function ‘void invers(int, int, int)’: user.cpp:79:33: warning: ‘dr1’ may be used uninitialized in this function [-Wmaybe-uninitialized] for(int i = st1; i<=(st1+dr1)/2; ++i) swap(v[i], v[dr1 - i + st1]); ^ user.cpp:79:33: warning: ‘st1’ may be used uninitialized in this function [-Wmaybe-uninitialized]