{"trustable":false,"sections":[{"title":"","value":{"format":"HTML","content":"Bessie搬到了一个新的农场,有时候他会回去看他的老朋友。但是他不想很快的回去,他喜欢欣赏沿途的风景,所以他会选择次短路,因为她知道一定有一条次短路。\u003cbr\u003e\n这个乡村有R(1\u003c\u003dR\u003c\u003d100000)条双向道路,每一条连接N(1\u003c\u003dN\u003c\u003d5000)个点中的两个。Bessie在1号节点,他的朋友家是n号节点"}},{"title":"Input","value":{"format":"HTML","content":"第一行:两个整数N和R\u003cbr\u003e\n接下来R行:每行包含三个整数,A,B,D,表示一条连接A与B的长度为D的路径"}},{"title":"Output","value":{"format":"HTML","content":"输出1到n的次短路"}},{"title":"Sample Input","value":{"format":"HTML","content":"\u003cpre class\u003d\"sio\"\u003e4 4\n1 2 100\n2 4 200\n2 3 250\n3 4 100\u003c/pre\u003e"}},{"title":"Sample Output","value":{"format":"HTML","content":"\u003cpre class\u003d\"sio\"\u003e450\u003c/pre\u003e"}},{"title":"Hint","value":{"format":"HTML","content":"\n \u003cdiv class\u003d\"ptx\" lang\u003d\"en-US\"\u003e\n Two routes: 1 -\u0026gt; 2 -\u0026gt; 4 (length 100+200\u003d300) and 1 -\u0026gt; 2 -\u0026gt; 3 -\u0026gt; 4 (length 100+250+100\u003d450)\n \u003c/div\u003e"}}]}