$ perl -e '
    use strict;
    use warnings;
    use List::MoreUtils "zip";
    my @sorted = 1..5;
    my @M = map "M$_", @sorted;
    my @v = map "v$_", @sorted[0..$#sorted-1];
    print join "->", grep defined, zip @M, @v;
'
M1->v1->M2->v2->M3->v3->M4->v4->M5