tight online conflict-free coloring of intervals

This study revisited the problem of online con ict-free coloring of intervals on a line, where each newly inserted interval must be assigned a color upon insertion such that the coloring remains con ict-free, i.e., for each point p in the union of the current intervals, there must be an interval i with a unique color among all intervals covering p. the bestknown algorithm uses o(log3 n) colors, where n is the number of current intervals. a simple greedy algorithm was presented that used only o(log n) colors. therefore, the open problem raised in [abam, m.a., rezaei seraji, m.j., and shadravan, m. online con ictfree coloring of intervals, journal of scientia iranica, 21(6), pp. 2138{2141 (2014).] was resolved.