Compilare: main.cpp: In function 'void preusu()': main.cpp:24:21: warning: array subscript has type 'char' [-Wchar-subscripts] lin[v[k]].push_back(i); ^ main.cpp:30:42: warning: array subscript has type 'char' [-Wchar-subscripts] for(int i=1;i<=n;++i) col[a[i][j]].push_back(j); ^ main.cpp: In function 'int main()': main.cpp:43:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(lin[t].size()<k) ~~~~~~~~~~~~~^~ main.cpp:52:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(col[t].size()<k) ~~~~~~~~~~~~~^~