Compilare: main.cpp: In function 'int main()': main.cpp:13:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < pat.size()) ~~^~~~~~~~~~~~ main.cpp:22:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < txt.size()) ~~^~~~~~~~~~~~ main.cpp:26:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (j == pat.size()) ~~^~~~~~~~~~~~~ main.cpp:28:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] else if (i < txt.size() && pat[j] != txt[i]) ~~^~~~~~~~~~~~ main.cpp:28:17: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses] else if (i < txt.size() && pat[j] != txt[i]) ^