68. 核酸检测

const readline = require('readline');
const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
});

let lineCount = 0;
let N = 0;
let confirmdCases = [];
let contacts = [];
let visited = [];

rl.on('line', function(line) {
    if (lineCount === 0) {
        N = parseInt(line);
        visited = new Array(N).fill(false);
    } else if(lineCount === 1) {
        confirmdCases = line.split(',').map(Number);
        contacts = new Array(N).fill(null).map(() => new Array(N).fill(false));
    } else {
        let row = line.split(',').map(Number);
        contacts[lineCount - 2] = row.map(v => v===1);
        if (lineCount - 2 === N - 1) {
            rl.close();
        }
    }
    lineCount++;
});
rl.on('close', () => {
    confirmdCases.forEach(i => dfs(contacts, visited, i));
    let count = 0;
    visited.forEach((hasVisited, i) => {
        if (hasVisited && !confirmdCases.includes(i)) {
            count++;
        }
    })
    console.log(count);
})

function dfs(contacts, visited, start) {
    visited[start] = true;
    for(let i=0; i<contacts.length; i++) {
        if (contacts[start][i] && !visited[i]) {
            dfs(contacts, visited, i);
        }
    }
}