描述

　　Traveling Salesman Problem



　　市场上有很多种商品，旅行商Shrek做短期买卖赚取差价。他从一个城市购买一件商品，到达下一个相邻的城市就卖掉。如果这一次买卖无利可图，那么他就不会这么走。凭着自己和同伴多年的经验，他已经对地图上n个城市之间的差价了如指掌。两城市间可能有多种商品可赚取差价，此时Shrek只好倒卖利润最大的一件商品。



　　现在请你帮Shrek规划一条路线，使他能赚最多的钱。



输入

　　第一行两个整数n、m。表示有n个城市，编号1~n



　　接下来有m行，每行三个整数a、b、price，表示从城市a到城市b可赚取差价price。



输出

　　若干Tab分隔的整数，连成一条赚钱最多的路线。若有多条，输出字典序最小的那条路线（编号小的城市靠前的路线优先输出）-descr iption

Traveling Salesman Problem



There are a variety of goods on the market, short-term trading TSP Shrek do make the difference. He bought a piece of merchandise　the city, arriving at a neighboring city to sell. If this is a profitable business, then he would not just leave. With their years of experience and his companions, he was well aware of the difference between n cities on the map. There may be a variety of goods between the two cities can make the difference, when Shrek had the biggest profit reselling a commodity.



Now you help Shrek planning a route, so that he can earn the most money.



enter

The first line of two integers n, m. He expressed n cities, numbered 1 ~ n



Then there are m rows, each row of three integers a, b, price, expressed　a city to city b can make the difference price.



Export

Several Tab separated integers, and even into a most profitable routes. If multiple output lexicographically smallest that route (a small number of priority urban