perechi2.cpp: In function `void read()': perechi2.cpp:37: warning: comparison between signed and unsigned integer expressions perechi2.cpp:39: warning: comparison between signed and unsigned integer expressions perechi2.cpp: In function `void solve()': perechi2.cpp:44: warning: comparison between signed and unsigned integer expressions perechi2.cpp:45: warning: comparison between signed and unsigned integer expressions perechi2.cpp:47: warning: comparison between signed and unsigned integer expressions perechi2.cpp:48: warning: comparison between signed and unsigned integer expressions