Solve the "Find the Celebrity" problem?

public int FindCelebrity(int n, Func<int, int, bool> knows) {
int candidate = 0;
for (int i = 1; i < n; i++) {
if (knows(candidate, i)) candidate = i;
}
for (int i = 0; i < n; i++) {
if (i != candidate && (knows(candidate, i) || !knows(i,

candidate)))

return -1;
}
return candidate;
}

Explanation:

First find candidate by elimination, then verify candidate.

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