#include <iostream>
#include <string>
#include <vector>
using namespace std;
int check[201]={};
void DFS(int k,int n,vector<vector<int>> computers){
if(check[k]==1)
return ;
check[k]=1;
for(int i=0;i<n;i++){
if(computers[i][k]==1){
computers[i][k]=0;
computers[k][i]=0;
DFS(i,n,computers);
}
}
}
int solution(int n, vector<vector<int>> computers) {
int answer=0;
for(int i=0;i<n;i++){
computers[i][i]=0;
}
for(int i=0;i<n;i++){
if(check[i]==0)
answer++;
for(int j=0;j<n;j++){
if(computers[i][j]==1){
computers[i][j]=0;
DFS(j,n,computers);
}
}
}
return answer;
}
https://school.programmers.co.kr/learn/courses/30/lessons/43162