플로이드

WEEK11/백준_11404_플로이드/oliver.swift

@@ -0,0 +1,50 @@
+let INF = 100_000 * 100 + 1
+let n = Int(readLine()!)!
+let m = Int(readLine()!)!
+
+// 인접리스트
+var graph: [[(node: Int, weight: Int)]] = Array(repeating: [], count: n+1)
+for _ in 0..<m {
+    let line = readLine()!.split(separator: " ").compactMap { Int($0) }
+    let (a, b, c) = (line[0], line[1], line[2])
+
+    graph[a].append((node: b, weight: c))
+}
+
+// dist 초기화
+var dist: [[Int]] = Array(repeating: Array(repeating: INF, count: n+1), count: n+1)
+for i in 1...n {
+    dist[i][i] = 0
+}
+
+// graph 순회하면서 dist행렬 채우기
+for i in 1...n {
+    for edge in graph[i] {
+        let destination = edge.node
+        let weight = edge.weight
+
+        dist[i][destination] = min(weight, dist[i][destination])
+    }
+}
+
+// 플로이드
+for k in 1...n {
+    for i in 1...n {
+        for j in 1...n {
+            dist[i][j] = min(dist[i][j], dist[i][k] + dist[k][j])
+        }
+    }
+}
+
+// 출력
+for i in 1...n {
+    var row: [String] = []
+    for j in 1...n {
+        if dist[i][j] == INF {
+            row.append("0")
+        } else {
+            row.append(String(dist[i][j]))
+        }
+    }
+    print(row.joined(separator: " "))
+}