Compilare: main.cpp: In function 'int main()': main.cpp:26:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=1;i<str1.length();++i) ~^~~~~~~~~~~~~~ main.cpp:31:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<str1.length();++i) ~^~~~~~~~~~~~~~ main.cpp:44:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=str1.length();i<str2.length();++i) ~^~~~~~~~~~~~~~