Compilare: user.cpp: In function ‘int main()’: user.cpp:10:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "cifra.in", "r", stdin ); ^ user.cpp:11:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "cifra.out", "w", stdout ); ^ user.cpp:16:24: warning: ‘n’ is used uninitialized in this function [-Wuninitialized] for ( int i = 0; i < n; i ++ ) { ~~^~~