이슈 #425에서 솔루션 추가

Author: actions-user

Programmers/섬_연결하기.cpp

@@ -0,0 +1,65 @@
+#include <vector>
+#include <algorithm>
+
+using namespace std;
+
+class DisjointSet {
+private:
+    vector<int> parent;
+    vector<int> rank;
+    
+public:
+    DisjointSet(int n) {
+        parent.resize(n);
+        rank.resize(n, 0);
+        for(int i = 0; i < n; i++) {
+            parent[i] = i;
+        }
+    }
+    
+    int find(int x) {
+        if(parent[x] != x) {
+            parent[x] = find(parent[x]);
+        }
+        return parent[x];
+    }
+    
+    void unionSet(int x, int y) {
+        int rootX = find(x);
+        int rootY = find(y);
+        
+        if(rootX == rootY) return;
+        
+        if(rank[rootX] < rank[rootY]) {
+            parent[rootX] = rootY;
+        } else {
+            parent[rootY] = rootX;
+            if(rank[rootX] == rank[rootY]) {
+                rank[rootX]++;
+            }
+        }
+    }
+};
+
+int solution(int n, vector<vector<int>> costs) {
+    // 비용 기준으로 정렬
+    sort(costs.begin(), costs.end(), [](const vector<int>& a, const vector<int>& b) {
+        return a[2] < b[2];
+    });
+    
+    DisjointSet ds(n);
+    int totalCost = 0;
+    
+    for(const auto& cost : costs) {
+        int from = cost[0];
+        int to = cost[1];
+        int weight = cost[2];
+        
+        if(ds.find(from) != ds.find(to)) {
+            ds.unionSet(from, to);
+            totalCost += weight;
+        }
+    }
+    
+    return totalCost;
+}