Compilare: user.cpp: In function ‘void read()’: user.cpp:18:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<n; i++) ^ user.cpp: In function ‘void solve()’: user.cpp:25:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=2; i<=n; i++) ^ user.cpp:27:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j+i-1<n; j++) ^