Compilare: user.cpp: In lambda function: user.cpp:31:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(p1 < oth[0].size() && p2 < oth[i].size()) ^ user.cpp:31:58: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(p1 < oth[0].size() && p2 < oth[i].size()) ^ user.cpp: In function ‘int main()’: user.cpp:40:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int p1 = 0, p2 = 0; p1 < oth[0].size() && p2 < oth[who].size(); ++p1, ++p2) ^ user.cpp:40:70: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int p1 = 0, p2 = 0; p1 < oth[0].size() && p2 < oth[who].size(); ++p1, ++p2) ^ user.cpp:50:52: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(cuv == itr && num < oth[0].size() && oth[0][num] == cuv) { ^ user.cpp:61:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<match.size();++i) ^ user.cpp:65:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<match.size();++i) { ^ user.cpp:78:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v.size();++i) { ^ user.cpp:60:9: warning: unused variable ‘nrn’ [-Wunused-variable] int nrn=0; ^