Compilare: user.cpp: In function ‘bool verify(line1)’: user.cpp:131:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < pts.size(); ++i) { ^ user.cpp:147:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < lst1.size(); ++i) { ^ user.cpp: In function ‘int main()’: user.cpp:172:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < pts.size(); ++i) { ^ user.cpp:173:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i + 1 == pts.size() || !same_point(pts[i], pts[i + 1])) ^ user.cpp:177:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (j + 1 < pts.size() && same_point(pts[i], pts[j + 1])) ^ user.cpp:188:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (hul.size() > aux && ccw(pts[hul[hul.size() - 2]], pts[hul.back()], pts[i]) > 0) ^ user.cpp:197:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (hul.size() > aux && ccw(pts[hul[hul.size() - 2]], pts[hul.back()], pts[i]) > 0) ^ user.cpp:215:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i < (hul.size() >> 1)) { ^ user.cpp:227:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ans.size(); ++i) { ^ user.cpp:238:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < ans.size(); ++i) { ^