Compilare: user.cpp: In function ‘void read()’: user.cpp:25: warning: comparison between signed and unsigned integer expressions user.cpp:27: warning: suggest parentheses around ‘&&’ within ‘||’ user.cpp:30: warning: comparison between signed and unsigned integer expressions user.cpp:45: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void solve(int)’: user.cpp:74: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:98: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result