var input = require("fs").readFileSync("input.txt").toString().replace("\n", "");
var nums = input.split(" ").map(a=>(parseInt(a)));

function parseTree(ints){
	var numChildren = ints[0];
	var numMeta = ints[1];
	var children = [];

	var i = 0;
	while(numChildren > 0){
		var childParsed = parseTree(ints.slice(2 + i));
		i += childParsed[1].length;
		children.push(childParsed[0]);
		numChildren--;
	}
	return [{children: children, meta: ints.slice(2+i, 2+i+numMeta)}, ints.slice(0, 2+i+numMeta)]
}

function nodeValue(node){
	var total = 0;
	if(node.children.length){
		return node.meta.map(a=>(a-1)).map(a=>(node.children[a])).filter(a=>(a)).map(n=>(nodeValue(n))).reduce((a,b)=>(a+b), 0);
	}
	else{
		return node.meta.reduce((a,b)=>(a+b));
	}
}

console.log(nodeValue(parseTree(nums)[0]));