Suppose we have a list of votes, where each element in the list has two elements [c_id, v_id], the c_id is the candidate id and v_id is the voter id. We have to check whether any voter has voted more than once or not.
So, if the input is like [[5, 1],[5, 0],[5, 4],[5, 3],[5, 0]], then the output will be True as [5,0] is present twice
To solve this, we will follow these steps −
make a new set named all
- for each vote in votes, do
- insert (vote[1]) into all
- return true when size of all is not same as size of votes
Let us see the following implementation to get better understanding −
Example
class Solution: def solve(self, votes): all = set() for vote in votes: all.add(vote[1]) return len(all) != len(votes) ob = Solution() votes = [[5, 1],[5, 0],[5, 4],[5, 3],[5, 0]] print(ob.solve(votes))
Input
[[5, 1],[5, 0],[5, 4],[5, 3],[5, 0]]
Output
True