Calculate index and add to feedback arc set

generator.c

@@ -200,30 +200,48 @@ int findIndex(int array[], int value, int size)
 	return (index == size ? -1 : index);
 }
 
-void genSolution(int permutation[])
+void genSolution(int permutation[], int V)
 {
 	int r;
 
 	// initialize array to indices
-	for (int i = 0; i < graph.V; i++) {
+	for (int i = 0; i < V; i++) {
 		permutation[i] = i;
 	}
 
 	// loop from end to start, choose random and switch
 	// with number at current index.
-	for (int i = (graph.V - 1); i > 0; i--) {
+	for (int i = (V - 1); i > 0; i--) {
 		r = rand() % (i+1);
 		int tmp = permutation[r];
 		permutation[r] = permutation[i];
 		permutation[i] = tmp;
 	}
 
-	for (int u = 0; u < graph.V; u++) {
+	int edges[MAX_ITEMS] = {-1};
+	int count = 0;
+
+	for (int u = 0; u < V; u++) {
+		int idx = findIndex(permutation, u, V);
 		struct AdjListNode *pCrawl = graph.array[u].head;
 		while (pCrawl) {
+			int idx_v = findIndex(permutation, pCrawl->dest, V);
+			if (idx > idx_v) {
+				edges[count++] = u;
+				edges[count++] = pCrawl->dest;
+				if (count > MAX_ITEMS)
+					return;
+				break;
+			}
+			pCrawl = pCrawl->next;
+		}
+	}
 
+	printf("[");
+	for (int i = 0; i < (count - 1); i++) {
+		printf("%d, ", edges[i]);
 	}
-	}
+	printf("%d]\n", edges[count-1]);
 }
 
 int main(int argc, char *argv[])
@@ -262,18 +280,14 @@ int main(int argc, char *argv[])
 
 	parse(argc, argv);
 
-	srand(time(NULL));
+	// seed differently for each process
+	srand(time(NULL) * getpid());
 
 	int permutation[graph.V];
 
 	while (quit == 0) {
-		for (int i = 0; i < 10; i++) {
-			genSolution(permutation);
-			printf("[");
-			for (int i = 0; i < (graph.V - 1); i++) {
-				printf("%d, ", permutation[i]);
-			}
-			printf("%d]\n", permutation[graph.V-1]);
+		for (int i = 0; i < 1000000; i++) {
+			genSolution(permutation, graph.V);
 		}
 		break;
 	}