Compilare: user.cpp: In function ‘void merge(int, int)’: user.cpp:23: warning: statement has no effect user.cpp:25: warning: statement has no effect user.cpp: In function ‘int main()’: user.cpp:45: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:46: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:48: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:50: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result