Compilare: main.cpp: In function 'std::__cxx11::string fct1()': main.cpp:26:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<b.size(); i++) ~^~~~~~~~~ main.cpp:39:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<b.size(); i++) ~^~~~~~~~~ main.cpp:47:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<b.size(); i++) ~^~~~~~~~~ main.cpp:64:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<a.size(); i++) ~^~~~~~~~~ main.cpp: In function 'std::__cxx11::string fct2()': main.cpp:79:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<b.size(); i++) ~^~~~~~~~~ main.cpp:92:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<b.size(); i++) ~^~~~~~~~~ main.cpp:100:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<b.size(); i++) ~^~~~~~~~~ main.cpp: In function 'std::__cxx11::string fct3()': main.cpp:129:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<b.size(); i++) ~^~~~~~~~~ main.cpp:142:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<b.size(); i++) ~^~~~~~~~~ main.cpp:150:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<b.size(); i++) ~^~~~~~~~~ main.cpp: In function 'int main()': main.cpp:174:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(ind<s.size()) ~~~^~~~~~~~~ main.cpp:206:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<it.size();i++){ ~^~~~~~~~~~