SRM595 Div2 500

LittleElephantAndIntervalsDiv2.py

class LittleElephantAndIntervalsDiv2:
    def getNumber(self, M, L, R):
        s = set()
        count = 0
        for i in reversed(xrange(0, len(L))):
            is_paint = False
            for n in range(L[i], R[i]+1):
                if n not in s:
                    is_paint = True
                s.add(n)
            else:
                if is_paint:
                    count += 1
        return pow(2, count)