Compilare: main.cpp: In function 'void KMP(std::__cxx11::string, std::__cxx11::string)': main.cpp:28:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 1; i < pat.size(); ++i ) ~~^~~~~~~~~~~~ main.cpp:41:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( i < A.size() ) { ~~^~~~~~~~~~ main.cpp:47:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if( j == pat.size() ) { ~~^~~~~~~~~~~~~ main.cpp:54:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if( i < A.size() && pat[j] != A[i] ) ~~^~~~~~~~~~ main.cpp:54:12: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses] if( i < A.size() && pat[j] != A[i] ) ^ main.cpp: In function 'void Do()': main.cpp:64:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < pat.size() && onlystar; ++i ) ~~^~~~~~~~~~~~ main.cpp:70:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < pat.size() && !star; ++i ) ~~^~~~~~~~~~~~ main.cpp:86:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < pat.size(); ++i ) { ~~^~~~~~~~~~~~ main.cpp:104:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 1; i < v.size(); ++i ) { ~~^~~~~~~~~~ main.cpp:109:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if( j == v[i].size() ) { fout << "-1"; return; } ~~^~~~~~~~~~~~~~