从城市a到达城市b，或从城市b到达城市a，价格为c。(0&lt;=a,b&lt;n,a与b不相等，0&lt;=c&lt;=1000)</span></div>
<div style="layout-grid-mode: char; text-indent: 21pt"><span style="font-size: medium">&nbsp;</span></div></div></div></div></div></div><div class="row"><div class="column"><h4 class="ui top attached block header">输出格式</h4><div class="ui bottom attached segment font-content"><div style="position: relative; overflow: hidden;"><div class=content><div style="layout-grid-m