Compilare: main.cpp: In function 'void calc_z(std::string&, std::string&)': main.cpp:14:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 14 | for(int i=1; i<str.size(); i++) | ~^~~~~~~~~~~ main.cpp:17:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 17 | while(i+z[i]<str.size() && str[z[i]]==str[i+z[i]]) | ~~~~~~^~~~~~~~~~~ main.cpp:25:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 25 | for(int i=0; i<s1.size(); i++) | ~^~~~~~~~~~ main.cpp:34:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 34 | for(int i=1; i<str.size(); i++) | ~^~~~~~~~~~~ main.cpp:37:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 37 | while(i+r_z[i]<str.size() && str[r_z[i]]==str[i+r_z[i]]) | ~~~~~~~~^~~~~~~~~~~ main.cpp:46:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 46 | for(int i=0; i<s1.size(); i++) | ~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:63:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 63 | if(x>0 && y<s1.size()-1) ans=min(z[y+1], r_z[x-1]); | ~^~~~~~~~~~~~