Compilare: user.cpp: In function ‘int main()’: user.cpp:130:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("schi.in", "r", stdin); ^ user.cpp:131:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("schi.out", "w", stdout); ^ user.cpp:132:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:134:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i]); ^ user.cpp: In function ‘int binary(int)’: user.cpp:125:9: warning: ‘last’ may be used uninitialized in this function [-Wmaybe-uninitialized] return last; ^ user.cpp: In function ‘int main()’: user.cpp:94:2: warning: ‘last’ may be used uninitialized in this function [-Wmaybe-uninitialized] for(int i=pos; i<=n; i+=lsb(i)) ^ user.cpp:108:6: note: ‘last’ was declared here int last; ^