Compilare: user.cpp: In function ‘char pereche(char)’: user.cpp:34:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:77:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &n); ^ user.cpp:78:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ /tmp/cc53pL8B.o: In function `main': user.cpp:(.text.startup+0x2d): warning: the `gets' function is dangerous and should not be used.