latex 显示效果
\uparrow ↑
\downarrow ↓
\Uparrow ⇑
\Downarrow ⇓
\updownarrow ↕
\Updownarrow ⇕
\rightarrow →
\leftarrow ←
\Rightarrow ⇒
\Leftarrow ⇐
\leftrightarrow ↔
\Leftrightarrow ⇔
\longrightarrow ⟶
\longleftarrow ⟵
\Longrightarrow ⟹
\Longleftarrow ⟸
\longleftrightarrow ⟷
\Longleftrightarrow ⟺
\mapsto ↦
\longmapsto ⟼
\hookleftarrow ↩
\hookrightarrow ↪
\leftharpoonup ↼
\rightharpoonup ⇀
\leftharpoondown ↽
\rightharpoondown ⇁
\rightleftharpoons ⇌
\leadsto ⇝
\nearrow ↗
\searrow ↘
\swarrow ↙
\nwarrow ↖
\nleftarrow ↚
\nrightarrow ↛
\nLeftarrow ⇍
\nRightarrow ⇏
\nleftrightarrow ↮
\nLeftrightarrow ⇎
\dashrightarrow ⇢
\dashleftarrow ⇠
\leftleftarrows ⇇
\leftrightarrows ⇆
\Lleftarrow ⇚
\twoheadleftarrow ↞
\leftarrowtail ↢
\looparrowleft ↫
\leftrightharpoons ⇋
\curvearrowleft ↶
\circlearrowleft ↺
\Lsh ↰
\upuparrows ⇈
\upharpoonleft ↿
\downharpoonleft ⇃
\multimap ⊸
\leftrightsquigarrow ↭
\rightrightarrows ⇉
\rightleftarrows ⇄
\rightrightarrows ⇉
\rightleftarrows ⇄
\twoheadrightarrow ↠
\rightarrowtail ↣
\looparrowright ↬
\rightleftharpoons ⇌
\curvearrowright ↷
\circlearrowright ↻
\Rsh ↱
\downdownarrows ⇊
\upharpoonright ↾
\downharpoonright ⇂
\rightsquigarrow ⇝