Compilare: user.cpp: In function ‘int main()’: user.cpp:28:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<pt.size(); ++i) { ^ user.cpp:47:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v.size(); ++i) { ^ user.cpp:50:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=1; j<v[i].size(); ++j) { ^ user.cpp:59:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0, j=0; i<v.size() && j<tx.size(); ++i, ++j) { ^ user.cpp:59:47: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0, j=0; i<v.size() && j<tx.size(); ++i, ++j) { ^ user.cpp:61:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(; j<tx.size(); ++j) { ^ user.cpp:66:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(q==v[i].size()-1) ^ user.cpp:69:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(q==v[i].size()-1) { ^ user.cpp:11:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("potrivire.in", "r", stdin); ^ user.cpp:12:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("potrivire.out", "w", stdout); ^