Compilare: user.cpp: In function ‘int main()’: user.cpp:93:7: warning: unused variable ‘rez’ [-Wunused-variable] int rez = common_prefix(a[j][kk], b[i], p); ^ user.cpp:75:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sabin.in", "r", stdin); ^ user.cpp:76:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sabin.out", "w", stdout); ^