Compilare: main.cpp: In function 'int main()': main.cpp:52:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0;i < euler.size();++i) ~~^~~~~~~~~~~~~~ main.cpp:55:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] mp[make_pair(euler[i], euler[i + 1 == euler.size() ? 0 : i + 1])] = i; ~~~~~~^~~~~~~~~~~~~~~ main.cpp:58:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 2;i <= euler.size();++i) ~~^~~~~~~~~~~~~~~ main.cpp:68:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int p = 1;(1 << p) <= euler.size();++p) ~~~~~~~~~^~~~~~~~~~~~~~~ main.cpp:69:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0;i + (1 << p) - 1 <= euler.size();++i) ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~ main.cpp:74:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0;j < wh[i].size();++j) ~~^~~~~~~~~~~~~~ main.cpp:76:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] int a = wh[i][j], b = wh[i][j + 1 == wh[i].size() ? 0 : j + 1]; ~~~~~~^~~~~~~~~~~~~~~