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答案1
先给你一个开始。在尝试寻找答案时,我偷用了 @cfr 的许多精彩答案(当然,这些答案都得到了点赞)。希望他/她能给你提供一个不那么笨拙的解决方案。
\documentclass[tikz,border=10pt]{standalone}
% stolen from nice cfr answers such as https://tex.stackexchange.com/a/278184/121799
\usepackage{forest}
\begin{document}
\begin{forest}
anchors/.style={anchor=#1,child anchor=#1,parent anchor=#1},
/tikz/every node/.append style={font=\footnotesize},
for tree={
s sep=5mm,l=15mm,
if n=0{anchors=east}{
if n=1{anchors=east}{anchors=west}},
content format={$\forestoption{content}$},
},
anchors=south, outer sep=2pt,
nodot/.style={content format={},draw=none},
dot/.style={tikz+={\draw[#1](.anchor)circle[radius=2pt];}},
if content={}{}{dot={fill}}
[\phi,dot=fill
[y_{1,1},dot=fill
[y_{1,1}y_{2,1},dot=fill
[,edge=dashed]
[,edge=dashed]]
[y_{1,1}y_{2,2},dot=fill
[,edge=dashed]
[,edge=dashed]]
[,edge=dashed]
[y_{1,1}y_{2,{m_2}},dot=fill
[,edge=dashed]
[,edge=dashed]]
]
[y_{1,1},dot=fill
[,edge=dashed]
[,edge=dashed]
]
[y_{1,{m_1}},dot=fill
[y_{{m_1},1}y_{2,1},dot=fill
[,edge=dashed]
[,edge=dashed]]
[y_{{m_1},1}y_{2,2},dot=fill
[,edge=dashed]
[,edge=dashed]]
[,edge=dashed]
[y_{{m_1},1}y_{2,{m_2}},dot=fill
[,edge=dashed]
[,edge=dashed]]
]
]
]
\end{forest}
\end{document}