Compilare: main.cpp: In function 'void add(trie*, int, int, int)': main.cpp:23:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(pos==s.size()) ~~~^~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:47:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<s.size();j++) ~^~~~~~~~~ main.cpp:54:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<s.size()-1 && ans>0;j++) ~^~~~~~~~~~~