Compilare: user.cpp: In function 'void df1(int)': user.cpp:52: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'void df2(int)': user.cpp:66: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'void df3(int)': user.cpp:78: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'void df4(int)': user.cpp:96: warning: comparison between signed and unsigned integer expressions user.cpp:91: warning: unused variable 'j' user.cpp: In function 'void solve()': user.cpp:158: warning: comparison between signed and unsigned integer expressions user.cpp:181: warning: comparison between signed and unsigned integer expressions user.cpp:197: warning: comparison between signed and unsigned integer expressions user.cpp:203: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'int solution(int, int)': user.cpp:219: warning: unused variable 'i' user.cpp: In function 'void writedata()': user.cpp:242: warning: operation on 'v1' may be undefined