I need part B to be in C language please thank you

Joint suffix tree

A). Draw a joint suffix tree for three strings ACTAC, ATCAT, TCACT. Label the edges and terminal nodes.

B). Describe an efficient algorithm to find the minimum length l for a set of strings T1, T2, . . ., Tk, such that there exist a unique signature substring of length l for each string. For example, if T1 = ACGACGTA, T2 = ACTATGAC, and T3 = GATAGTA, the smallest l = 2, since a signature of length 2 can be found for each string: CG only appears in T1, CT only in T2 and AG only in T3, and there is no unique substring of length 1 for all sequences.