// driver program to test above function
int main()
{
/* Let us create the following weighted graph
10
(0)------->(3)
| /|\
5 | |
| | 1
\|/ |
(1)------->(2)
3 */
int graph[V][V] = { {0, 3, INF, INF},
{3, 0, 4, INF},
{INF, 4, 0, 5},
{INF, INF, 5, 0}
};
// Print the solution
floydWarshell(graph);
return 0;
}
// driver program to test above function
int main()
{
int i=0,j=0;
char line[100], member[100];
//int graph[V][V];
int **graph;
int shortest_i=-1,shortest_j=-1, shortest_len=INF;
fp = fopen("g1.txt", "r");
if (fp == NULL)
exit(1);
fgets(line, 100, fp); // Read the first line
printf("%s", line);
for (i = 0, j = 0; i < 100; i++) {
if(line[i] == ' ' || line[i] == '\0') {
member[j] = '\0';
j = 0;
if(num_vertices == -1)
num_vertices = atoi(member);
else if (num_edges == -1)
num_edges = atoi(member);
else {
printf("Error in num_Vertices line parsing %d\n", num_vertices);
exit(-1);
}
if(line[i] == '\0')
break;
}
else {
member[j] = line[i];
j++;
}
}
printf("Number of vertices: %d\n", num_vertices);
graph = (int**) malloc(num_vertices*(sizeof(int*)));
if(!graph) {
printf("Cannot alloc memory..Exiting\n");
exit(-1);
}
for (i = 0; i < num_vertices; i++){
graph[i] = (int *) malloc(num_vertices*sizeof(int));
if(!graph[i]) {
printf("Cannot alloc memory..Exiting\n");
exit(-1);
}
}
for(i = 0; i < num_vertices; i++)
for(j = 0; j < num_vertices; j++) {
if ( i == j)
graph[i][j] = 0;
else
graph[i][j] = INF;
}
//printmatrix(graph);
while (!feof(fp)) {
// Read file line by line
fgets(line, 100, fp);
// Line is of the form vertex1 vertex2 edge-cost
int vertex1=-1, vertex2=-1, edge=-1;
for (i = 0, j = 0; i < 100; i++) {
if(line[i] == ' ' || line[i] == '\0') {
member[j] = '\0';
j = 0;
if(vertex1 == -1)
vertex1 = atoi(member);
else if(vertex2 == -1)
vertex2 = atoi(member);
else if(edge == -1)
edge = atoi(member);
else {
printf("Error in line parsing\n");
exit(-1);
}
if(line[i] == '\0')
break;
}
else {
member[j] = line[i];
j++;
}
}
// Set entry in Graph
//printf("vertex1: %d Vertex2: %d edge: %d\n", vertex1, vertex2, edge);
graph[vertex1 -1][vertex2 - 1] = edge;
}
// compute
floydWarshell(graph);
// Detect if negative cycles
for (i = 0; i < num_vertices; i++) {
if(graph[i][i] < 0) {
printf("Negative cycle exists\n");
exit(0);
}
}
// Print soln
for (i = 0; i < num_vertices; i++) {
for (j = 0; j < num_vertices; j++) {
if(graph[i][j] < shortest_len) {
shortest_i = i;
shortest_j = j;
shortest_len = graph[i][j];
}
}
}
printf("Shortest path is from %d to %d with len %d\n", (shortest_i+1),(shortest_j+1), shortest_len);
return 0;
}
