CS153/hw6/hw5programs/sp22_tests/floyd_warshall.oat

struct Graph {
  AdjList?[] adj_lists
}

struct AdjList {
  Edge[] edges
}

struct Edge {
  int neighbor;
  int weight;
  bool neg
}

global e01 = new Edge { neighbor = 1; weight = 5; neg = true };
global e02 = new Edge { neighbor = 2; weight = 10; neg = false };
global e04 = new Edge { neighbor = 4; weight = 0; neg = false };
global e07 = new Edge { neighbor = 7; weight = 51; neg = false};

global e12 = new Edge { neighbor = 2; weight = 12; neg = false  };

global e23 = new Edge { neighbor = 3; weight = 3; neg = true };

global e34 = new Edge { neighbor = 4; weight = 5; neg = false  };
global e36 = new Edge { neighbor = 6; weight = 50; neg = false  };

global e40 = new Edge {neighbor = 0; weight = 1; neg = true };
global e45 = new Edge { neighbor = 5; weight = 100; neg = false  };

global e78 = new Edge { neighbor = 8; weight = 10; neg = false  };
global e710 = new Edge { neighbor = 10; weight = 5; neg = true};

global e89 = new Edge { neighbor = 9; weight = 3; neg = false  };

global e97 = new Edge { neighbor = 7; weight = 12; neg = false };
global e910 = new Edge { neighbor = 10; weight = 2; neg = true };

global e100 = new Edge {neighbor = 0; weight = 79; neg = false };

void print_int_array(int[][] arr) {
  for (var i = 0; i < length(arr); i = i + 1;) {
      for (var j = 0; j < length(arr[i]); j = j + 1;) {
          print_int(arr[i][j]);
          print_string(" ");
      }
  }
  return;
}

int[][] floyd_warshall(Graph graph) {
  var n = length(graph.adj_lists);
  var dist = new int[][n]{i -> new int[n]{j -> 999}};
  
  for (var i = 0; i < n; i = i+1;) {
      dist[i][i] = 0;
  }

    for (var i = 0; i < n; i = i + 1;) {
      if?(AdjList v = graph.adj_lists[i]) {
          var v_edges = v.edges; 
          for (var j = 0; j < length(v_edges); j = j + 1;) {
              var nbr = v_edges[j].neighbor;
              var weight = v_edges[j].weight;
              var negative = v_edges[j].neg;
              if (negative) {
                  weight = 0 - weight;
              }
              dist[i][nbr] = weight;
          }
      }
    }
    
    for (var k = 0; k < n; k = k + 1;) {
        for (var i = 0; i < n; i = i + 1;) {
            for (var j = 0; j < n; j = j + 1;) {
                if (dist[i][k] < 999 & (dist[k][j] < 999)) {
                    if (dist[i][k] + dist[k][j] < dist[i][j]) {
                        dist[i][j] = dist[i][k] + dist[k][j];
                    }
                }
            }
        }
    }
  return dist;
}

int program (int argc, string[] argv) {
  var a0 = new AdjList { edges = new Edge[]{e01, e02, e04, e07} };
  var a1 = new AdjList { edges = new Edge[]{e12} };
  var a2 = new AdjList { edges = new Edge[]{e23} };
  var a3 = new AdjList { edges = new Edge[]{e34, e36} };
  var a4 = new AdjList { edges = new Edge[]{e45, e40} };
  var a5 = AdjList null;
  var a6 = AdjList null;
  var a7 = new AdjList { edges = new Edge[]{e78, e710} };
  var a8 = new AdjList { edges = new Edge[]{e89} };
  var a9 = new AdjList { edges = new Edge[]{e910, e97} };
  var a10 = new AdjList {edges = new Edge[]{e100} };

  var graph = new Graph { adj_lists = new AdjList?[]{a0, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10} };
  
  var result = floyd_warshall(graph)[0];
  for (var i = 0; i < 10; i = i + 1;) {
      print_int(result[i]);
      print_string(" ");
  }
  return 0;
}