Compilare: user.cpp: In function ‘void read()’: user.cpp:11: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:13: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void df(int)’: user.cpp:26: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void df2(int)’: user.cpp:43: warning: comparison between signed and unsigned integer expressions user.cpp:46: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int cel(int)’: user.cpp:53: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void solve()’: user.cpp:68: warning: comparison between signed and unsigned integer expressions user.cpp:72: warning: comparison between signed and unsigned integer expressions user.cpp:83: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘int main()’: user.cpp:89: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:90: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result