Compilare: main.cpp: In function 'int main()': main.cpp:52:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0;i < euler.size();i++) ~~^~~~~~~~~~~~~~ main.cpp:55:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1;(1<<i) < euler.size();i++) ~~~~~~~^~~~~~~~~~~~~~ main.cpp:56:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j + (1 << i)-1 < euler.size(); j++) ~~~~~~~~~~~~~~~^~~~~~~~~~~~~~