Compilare: user.cpp: In function ‘int largest_prefix(int, int)’: user.cpp:12:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(pos==cuv.size()) ~~~^~~~~~~~~~~~ user.cpp:14:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<legaturi[nod].size();i++) ~^~~~~~~~~~~~~~~~~~~~~ user.cpp: In function ‘void add(int)’: user.cpp:24:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(counter!=cuv.size()) ~~~~~~~^~~~~~~~~~~~ user.cpp:27:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<legaturi[pos].size();i++) ~^~~~~~~~~~~~~~~~~~~~~ user.cpp:30:9: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i==legaturi[pos].size()) ~^~~~~~~~~~~~~~~~~~~~~~ user.cpp:51:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=counter;i<cuv.size();i++) ~^~~~~~~~~~~ user.cpp:55:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i+1<cuv.size()) ~~~^~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:68:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trie.in","r",stdin); ^ user.cpp:69:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("trie.out","w",stdout); ^ user.cpp:74:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %s\n",&c,aux); ^