Compilare: user.cpp: In function ‘int solve(int, int)’: user.cpp:19:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( dr != 1000000 && ( i < h[a].size() && j < h[b].size() ) ){ ^ user.cpp:19:64: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( dr != 1000000 && ( i < h[a].size() && j < h[b].size() ) ){ ^ user.cpp:21:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( i < h[a].size() && h[a][i].first <= dr + 1 ){ ^ user.cpp:25:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( j < h[b].size() && h[b][j].first <= dr + 1 ){ ^ user.cpp:37:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( dr != 1000000 && i < h[a].size() && h[a][i].first <= dr + 1 ){ ^ user.cpp:42:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( dr != 1000000 && j < h[b].size() && h[b][j].first <= dr + 1 ){ ^