Map to store index of elements
map < int , int > mp1 , mp2 ; for ( int i = 0 ; i < n ; i ++ ) { mp1 [ perm1 [ i ] ] = i ; } for ( int j = 0 ; j < n ; j ++ ) { mp2 [ perm2 [ j ] ] = j ; } for ( int i = 0 ; i < n ; i ++ ) {