Compilare: user.cpp: In function ‘bool drum()’: user.cpp:71: warning: comparison between signed and unsigned integer expressions user.cpp:77: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int back(int, int, int, int)’: user.cpp:147: warning: comparison between signed and unsigned integer expressions user.cpp:161: warning: comparison between signed and unsigned integer expressions user.cpp:164: warning: comparison between signed and unsigned integer expressions user.cpp:174: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void calcDrum()’: user.cpp:200: warning: comparison between signed and unsigned integer expressions user.cpp:201: warning: comparison between signed and unsigned integer expressions user.cpp:208: warning: comparison between signed and unsigned integer expressions user.cpp:213: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:254: warning: comparison between signed and unsigned integer expressions