Compilare: user.cpp: In function ‘int adun(std::string, char, int)’: user.cpp:14:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j<ss.size()) ^ user.cpp:24:43: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(ss[j]=='*' && j<ss.size()) ^ user.cpp:38:59: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(isdigit(ss[j]) && j<ss.size()) ^ user.cpp:68:47: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(isdigit(ss[j]) && j<ss.size()) ^ user.cpp: In function ‘int main()’: user.cpp:117:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<s.size();i++) ^ user.cpp:134:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=2;j<s2.size();j++)x=x*10+(s2[j]-'0'); ^ user.cpp:142:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<s.size();i++) ^