Problem
补之前的
The country is facing a terrible civil war—cities in the country are divided into two parts supporting different leaders. As a merchant, Mr. M does not pay attention to politics but he actually knows the severe situation, and your task is to help him reach home as soon as possible. “For the sake of safety,”, said Mr.M, “your route should contain at most 1 road which connects two cities of different camp.” Would you please tell Mr. M at least how long will it take to reach his sweet home?
The input contains multiple test cases.
The first line of each case is an integer N (2<=N<=600), representing the number of cities in the country.
The second line contains one integer M (0<=M<=10000), which is the number of roads.
The following M lines are the information of the roads. Each line contains three integers A, B and T, which means the road between city A and city B will cost time T. T is in the range of [1,500].
Next part contains N integers, which are either 1 or 2. The ith integer shows the supporting leader of city i.
To simplify the problem, we assume that Mr. M starts from city 1 and his target is city 2. City 1 always supports leader 1 while city 2 is at the same side of leader 2.
Note that all roads are bidirectional and there is at most 1 road between two cities.
Input is ended with a case of N=0.
For each test case, output one integer representing the minimum time to reach home.
If it is impossible to reach home according to Mr. M’s demands, output 1 instead.
Examples:
Input:
2
1
1 2 100
1 2
3
3
1 2 100
1 3 40
2 3 50
1 2 1
5
5
3 1 200
5 3 150
2 5 160
4 3 170
4 2 170
1 2 2 2 1
0
Output:
100
90
540
Solutions
 单源最短路径问题，计算两次最短路，分别是计算阵营1里各点最短路径，和阵营2里各点最短路径，然后再遍历边界线上联通两个阵营的边，看哪个最短
C++ Codes
1 

总结
 不是模板题，需要注意下两个阵营不能一起使用dijkstra，而是应该分阵营计算好，然后加上边界的值，得到最短路劲
 dijkstra主要是两个for循环，最短路径，每次找距离源点最近的点加进去，维护的dis数组也是距离源点的数组