||p1||+||tl(p)||-1 
{||p1||..(||p1||+||tl(p)||)
} tl(p)[(||p1||+||tl(p)||-1-||p1||)] = z
i:
(||p1||-1). p1[i]-the_graph- > p1[(i+1)]
i:(||p||-1). p[i]-the_graph- > p[(i+1)]
(p1 @ tl(p))[(||p1 @ tl(p)||-1)] = z
as,bs:T List. ||as @ bs|| = ||as||+||bs|| 
0
as,bs:T List, i:{||as||..(||as||+||bs||)}. (as @ bs)[i] = bs[(i-||as||)]
0
| 1 | ||p1||+||tl(p)||-1 {||p1||..(||p1||+||tl(p)||)} | 1 step |
| 2 | tl(p)[(||p1||+||tl(p)||-1-||p1||)] = z | 4 steps |
About:
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