Problem URL: Dota2 senate

We will take 2 queues one for dire and one for radiants which keeps their indexes. We pop from both queue whichever is larger(y) index we will bann that. and append smaller_element (x)+ idx as this element will be candidate for next round.

class Solution:
    def predictPartyVictory(self, senate: str) -> str:
        R = collections.deque()
        D = collections.deque()

        n = len(senate)

        for idx, senator in enumerate(senate):
            R.append(idx) if senator == 'R' else D.append(idx)

        while R and D:
            x = R.popleft()
            y = D.popleft()

            R.append(x+n) if x<y else D.append(y+n)

        return "Radiant" if R else "Dire"

Time Complexity: O(n)
Space Complexity: O(n)