public class ShortestPathOfFloyd {
   private final static int VERTEX = 7;
   private final static int[][] MATRIX = new int[VERTEX][VERTEX];
   private final static int[][] PATH = new int[MATRIX.length][MATRIX.length];
   private final static int MAX_VALUE = 100000;
​
   /**
   * 初始化鄰接矩陣
   */
   static void initMatrix() {
     for (int i = 0; i < VERTEX; i++) {
       for (int j = 0; j < VERTEX; j++) {
         MATRIX[i][j] = MAX_VALUE;
       }
     }
   }
​
   /**
   * 初始化邊
   */
   static void initEdge() {
     MATRIX[0][1] = 6;
     MATRIX[0][3] = 2;
     MATRIX[1][2] = 5;
     MATRIX[1][5] = 3;
     MATRIX[3][4] = 5;
     MATRIX[3][1] = 7;
     MATRIX[4][6] = 1;
     MATRIX[5][4] = 2;
     MATRIX[5][2] = 3;
   }
​
   public static void main(String[] args) {
     initMatrix();
     initEdge();
     //呼叫演算法計算最短路徑
     floyd(MATRIX);
   }
​
   @SuppressWarnings("all")
   private static void floyd(int[][] matrix) {
     for (int i = 0; i < matrix.length; i++) {
       for (int j = 0; j < matrix.length; j++) {
         PATH[i][j] = -1;
       }
     }
     for (int m = 0; m < matrix.length; m++) {
       for (int i = 0; i < matrix.length; i++) {
         for (int j = 0; j < matrix.length; j++) {
           if (matrix[i][m] + matrix[m][j] < matrix[i][j]) {
             matrix[i][j] = matrix[i][m] + matrix[m][j];
             //記錄經由哪個點到達
             PATH[i][j] = m;
           }
         }
       }
     }
​
     for (int i = 0; i < matrix.length; i++) {
       getPath(matrix, 0, i);
     }
​
​
   }
​
   private static void getPath(int[][] matrix, int start, int destination) {
​
     if (matrix[start][destination] == MAX_VALUE) {
       System.out.println(start + "到" + destination + "不可達");
     } else {
       System.out.print(start + "到" + destination + "的最短路徑長度是：" + matrix[start][destination]);
       System.out.print("最短路徑為：" + start + "->");
       findPath(start, destination);
       System.out.println(destination);
     }
   }
​
   private static void findPath(int i, int j) {
     int m = PATH[i][j];
     if (m == -1) {
       return;
     }
     findPath(i, m);
     System.out.print(m + "->");
     findPath(m, j);
   }
​
}
​
 

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原文連結：https://blog.csdn.net/qq_34842671/article/details/90637502