Cs50 Tideman Solution

Think of the locked array as a directed graph. Each candidate is a node. When you lock a pair (winner → loser), you draw an arrow from the winner to the loser.

Once all votes are cast, the add_pairs function iterates through the preferences matrix. For every pair of candidates $(i, j)$:

The CS50 Tideman solution implements the Tideman algorithm in a program that allows users to vote, view the current standings, and determine the winner. Cs50 Tideman Solution

The winner is the candidate who has no incoming edges.

If found, update the ranks array where ranks[rank] equals the candidate's index. Return true if the vote is valid, and false otherwise. 2. Record Preferences Think of the locked array as a directed graph

You can use a simple Selection Sort or Bubble Sort since the candidate count is small (maximum of 9).

if (locked[j][i]) // If someone beats i

Unlike simpler voting systems, Tideman prevents the "spoiler effect" by creating a graph of voter preferences and locking in victories without creating cyclical loops.

// Base Case: If the target (end) can already reach the start, a cycle is found (start == end) Once all votes are cast, the add_pairs function

return false;

When starting your recursion, always look for a path leading from the loser of the current pair back to the winner of the current pair .