Compilare: main.cpp: In function 'void prefix()': main.cpp:14:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<a.size();i++) ~^~~~~~~~~ main.cpp: In function 'void KMP()': main.cpp:30:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j<b.size()) ~^~~~~~~~~ main.cpp:39:8: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i==a.size()) ~^~~~~~~~~~