{"trustable":false,"prependHtml":"\u003cstyle type\u003d\u0027text/css\u0027\u003e\n .input, .output {\n border: 1px solid #888888;\n }\n .output {\n margin-bottom: 1em;\n position: relative;\n top: -1px;\n }\n .output pre, .input pre {\n background-color: #EFEFEF;\n line-height: 1.25em;\n margin: 0;\n padding: 0.25em;\n }\n \u003c/style\u003e\n \u003clink rel\u003d\"stylesheet\" href\u003d\"//codeforces.org/s/96598/css/problem-statement.css\" type\u003d\"text/css\" /\u003e\n\u003cscript\u003e\n window.katexOptions \u003d {\n delimiters: [\n {left: \u0027$$$$$$\u0027, right: \u0027$$$$$$\u0027, display: true},\n {left: \u0027$$$\u0027, right: \u0027$$$\u0027, display: false},\n {left: \u0027$$\u0027, right: \u0027$$\u0027, display: true},\n {left: \u0027$\u0027, right: \u0027$\u0027, display: false}\n ]\n };\n\u003c/script\u003e\n","sections":[{"title":"","value":{"format":"HTML","content":"\u003cdiv\u003e\n 众所周知,强神喝多了喜欢睡觉,但是森神喝多了喜欢上树。我们可以认为树上有n个点,现在强神在某个点上睡觉,若森神距离强神\u0026lt;\u003dd那么森神就会带上强神的强buff,现在告诉你有m个点上森神感受到了强buff(其他位置不确定,可能有可能没有)问有哪些节点可能有强神在那睡觉(注意:强神只有一个!)\n\u003c/div\u003e"}},{"title":"Input","value":{"format":"HTML","content":"\u003cdiv\u003e \n \u003cdiv\u003e \n \u003cdiv\u003e\n \u0026nbsp;\n \u003cspan\u003e第一行n\u003c/span\u003e\u0026nbsp;m\u0026nbsp;d(1\u0026lt;\u003dm\u0026lt;\u003dn\u0026lt;\u003d100000)(0\u0026lt;\u003dd\u0026lt;\u003dn-1)\u0026nbsp;\n \u003cspan\u003e第二行输入p1到pm\u003c/span\u003e\u0026nbsp;(1\u0026lt;\u003dpi\u0026lt;\u003d\n \u003cspan\u003en)后面n-1行\u003c/span\u003e\u0026nbsp;\n \u003cspan\u003e每行两个数ai\u003c/span\u003e\u0026nbsp;bi\u0026nbsp;\n \u003cspan\u003e代表一条边\u003c/span\u003e\n \u003c/div\u003e \n \u003c/div\u003e \n\u003c/div\u003e"}},{"title":"Output","value":{"format":"HTML","content":"\u003cdiv\u003e \n \u003cdiv\u003e \n \u003cp\u003e \u003cspan\u003e一个整数\u003c/span\u003e \u003cspan\u003e代表\u003c/span\u003e \u003cspan\u003e强神可能睡觉的节点的数目\u003c/span\u003e\u003c/p\u003e \n \u003c/div\u003e \n\u003c/div\u003e"}},{"title":"Sample Input","value":{"format":"HTML","content":"\u003cdiv\u003e \n \u003cdiv\u003e \n \u003cdiv\u003e \n \u003cdiv\u003e \n \u003cdiv\u003e \n \u003cdiv\u003e\n 6 2 3\n \u003c/div\u003e \n \u003cdiv\u003e\n 1 2\n \u003c/div\u003e \n \u003cdiv\u003e\n 1 5\n \u003c/div\u003e \n \u003cdiv\u003e\n 2 3\n \u003c/div\u003e \n \u003cdiv\u003e\n 3 4\n \u003c/div\u003e \n \u003cdiv\u003e\n 4 5\n \u003c/div\u003e \n \u003cdiv\u003e\n 5 6\n \u003c/div\u003e \n \u003cdiv\u003e\n \u0026nbsp;\n \u003c/div\u003e \n \u003c/div\u003e \n \u003c/div\u003e \n \u003c/div\u003e \n \u003c/div\u003e \n\u003c/div\u003e"}},{"title":"Sample Output","value":{"format":"HTML","content":"\u003cp\u003e 3\u003c/p\u003e"}}]}