Compilare: user.cpp: In function ‘void create_arb(int, int, int)’: user.cpp:55:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (; i<arb[L].size(); ++i) ^ user.cpp:58:99: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if (v[arb[node][i]].x < v[arb[node][mini]].x || v[arb[node][i]].x == v[arb[node][mini]].x && v[arb[node][i]].y < v[arb[node][mini]].y) ^ user.cpp:62:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (; i<arb[L].size() + arb[R].size(); ++i) ^ user.cpp:65:99: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if (v[arb[node][i]].x < v[arb[node][mini]].x || v[arb[node][i]].x == v[arb[node][mini]].x && v[arb[node][i]].y < v[arb[node][mini]].y) ^ user.cpp:75:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<arb[node].size(); ++i) ^ user.cpp: In function ‘void query(int, int, int)’: user.cpp:128:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (mid != arb[node].size() - 1) ^ user.cpp:144:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] else if (mid == arb[node].size()-1) ^ user.cpp:162:12: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if (ans == -1) ^ user.cpp:133:17: warning: ‘val2’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (val >= val2) ^