Distinguishing Substring Selection Problem Instance: Given a set B of n, (bad) strings of length at least L, a setG of n,(good) strings, two thresholds db and < Objective: Find a string s such that for each string b E B there exists a substring t of b with lengthl such that d(S,1)≤db and for any string g∈G, (S,g)≥ Bad sequences s: motif Good sequences 2021/1/292021/1/29 3 Distinguishing Substring Selection Problem Instance: Given a set B of n1 (bad) strings of length at least L, a set G of n2 (good) strings, two thresholds db and dg ( db < dg ). Objective: Find a string s such that for each string b  B there exists a substring t of b with length L such that d(s, t)  db and for any string g  G, d(s, g)  dg . Bad sequences Good sequences s: motif