Compilare: user.cpp: In function ‘int LevenshteinDistance(std::string, std::string)’: user.cpp:14:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<=s1.length();i++) ^ user.cpp:16:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<=s2.length();i++) ^ user.cpp:19:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=1;j<=s2.length();j++) ^ user.cpp:20:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<=s1.length();i++) ^ user.cpp: In function ‘int main()’: user.cpp:40:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("edist.in", "r", stdin); ^ user.cpp:41:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("edist.out", "w", stdout); ^