Compilare: user.cpp: In function ‘int main()’: user.cpp:31:38: warning: narrowing conversion of ‘i’ from ‘int’ to ‘short int’ inside { } [-Wnarrowing] frec[v[i][j]].push_back({i , j}); ^ user.cpp:31:38: warning: narrowing conversion of ‘j’ from ‘int’ to ‘short int’ inside { } [-Wnarrowing] user.cpp:36:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0 ; j < frec[q[i]].size() ;j++){ ^