P revious and our results Problem Collision GI rap h Completion detection time arb Without Bidirectional Unsolvable arB Without Bidirectional(n22) Strongly connected(n22) O(n32) aRG Without Bidirectional (n22) O(nlogn) Strongly connected(n22) O(n3/2 n: number of nodes Our resultsPrevious and our results Problem Collision detection Graph Completion time ARB Without Bidirectional Unsolvable ARB Without Bidirectional (n≥2) O(n) Strongly connected (n≥2) O(n 3/2) ARG Without Bidirectional (n≥2) O(nlog3n) Strongly connected (n≥2) O(n 3/2) n: number of nodes Our results