[3] 섬 연결하기

#include <iostream>
#include <algorithm>
#include <vector>
 
using namespace std;
 
vector<int> vIsland(100);
 
bool Cmp(vector<int> a, vector<int> b) { return a[2] < b[2]; }
 
int FindParent(int idx)
{
    if (vIsland[idx] != idx)
        vIsland[idx] = FindParent(vIsland[idx]);
 
    return vIsland[idx];
}
 
int solution(int n, vector<vector<int>> costs)
{
    int answer = 0;
    sort(costs.begin(), costs.end(), Cmp);
 
    for (int i = 0; i < n; i++)
        vIsland[i] = i;
 
    for (int i = 0; i < costs.size(); i++)
    {
        int a = FindParent(costs[i][0]), b = FindParent(costs[i][1]), cost = costs[i][2];
 
        if (a != b)
        {
            answer += cost;
            vIsland[b] = a;
        }
    }
    return answer;
}