Compilare: user.cpp: In function ‘int df2(int)’: user.cpp:14: warning: comparison between signed and unsigned integer expressions user.cpp:27: warning: no return statement in function returning non-void user.cpp: In function ‘int df(int, int)’: user.cpp:36: warning: comparison between signed and unsigned integer expressions user.cpp:43: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:70: warning: comparison between signed and unsigned integer expressions user.cpp:73: warning: comparison between signed and unsigned integer expressions user.cpp:76: warning: comparison between signed and unsigned integer expressions user.cpp:82: warning: comparison between signed and unsigned integer expressions user.cpp:85: warning: comparison between signed and unsigned integer expressions user.cpp:88: warning: comparison between signed and unsigned integer expressions