Compilare: main.cpp: In function 'int Z(int, int)': main.cpp:26:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ main.cpp: In function 'int main()': main.cpp:39:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = -1; i <= N.length();) ~~^~~~~~~~~~~~~ main.cpp:30:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("telefon.in", "r", stdin); ^ main.cpp:31:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("telefon.out", "w", stdout); ^