OK, so I have an assignment due about graphs. We are to use the floyd warshall algorithum to find the diameter of each graph. I have some code for the algorithum, but I am getting some strange results. Using the graph info below, when I get to 0-7, instead of taking the 8, it finds the -1 part of the equation and skips the if statement. Anyone know what I need to add to avoid mistakes like this?
I know where the mistake is, but not the logical answer to it. I bolded it so you can find it fast. Any help will be appreciated.
Code:
void map::floyd()
{
//initalize path matrix
for(int i=0;i<MAX_NODES;i++)
{
for(int j=0;j<MAX_NODES;j++)
{
if(adj[i][j]!=-1)
path[i][j] = j;
else
path[i][j] = -1;
}
}
//floyd warshall alg
for(i=0;i<N;i++)
{
for(int j=0;j<N;j++)
{
for(int k=0;k<N;k++)
{
if((adj[i][j] > adj[i][k] + adj[k][j]) &&
(path[i][k] !=-1 && path[j][k] !=-1) &&
(adj[i][k] != -1 && adj[k][j] != -1))
{
adj[i][j] = adj[i][k] + adj[k][j];
//adj[j][i] = adj[i][j];
path[i][j] = path[i][k];
}
}
}
}
}
Code:
11 13
0 3 -1 -1 -1 12 10 -1 -1 -1 -1
1 -1 -1 -1 2 7 8 -1 -1 1
2 2 -1 -1 -1 -1 -1 8 -1
3 -1 -1 -1 -1 -1 4 -1
4 -1 -1 -1 -1 -1 -1
5 3 -1 -1 -1 -1
6 -1 5 -1 -1
7 5 -1 -1
8 -1 -1
9 -1
10
Linear Mode
