Compilare: main.cpp: In function 'void p1()': main.cpp:14:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i < s.size() - 1; i++) ~~^~~~~~~~~~~~~~ main.cpp: In function 'void p2()': main.cpp:32:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < s.size(); i++) ~~^~~~~~~~~~ main.cpp:48:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(prev_pos && next[next_pos] < s.size() && relation(s[prev_pos], s[next_pos], s[next[next_pos]])) main.cpp:50:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(prev[prev_pos] && next_pos < s.size() && relation(s[prev[prev_pos]], s[prev_pos], s[next_pos])) ~~~~~~~~~^~~~~~~~~~ main.cpp:53:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < s.size(); i = next[i]) ~~^~~~~~~~~~