Cowmpetency
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Farmer John is hiring a new herd leader for his cows. To that end, he has
interviewed \(N\) (\(2 \leq N \leq 10^5\)) cows for the position. After interviewing
the \(i\)th candidate, he assigned the candidate an integer "cowmpetency" score
\(c_i\) ranging from \(1\) to \(C\) inclusive (\(1 \leq C \leq 10^9\)) that is
correlated with their leadership abilities.
Because he has interviewed so many cows, Farmer John does not remember all of
their cowmpetency scores. However, he does remembers \(Q\) (\(1 \leq Q < N\)) pairs
of numbers \((a_j, h_j)\) where cow \(h_j\) was the first cow with a strictly
greater cowmpetency score than cows \(1\) through \(a_j\) (so
\(1 \leq a_j < h_j \leq N\)).
Farmer John now tells you the sequence \(c_1, \dots, c_N\) (where \(c_i = 0\) means
that he has forgotten cow \(i\)'s cowmpetency score) and the \(Q\) pairs of
\((a_j, h_j)\). Help him determine the lexicographically smallest sequence
of cowmpetency scores consistent with this information, or that no such sequence
exists! A sequence of scores is lexicographically smaller than another sequence
of scores if it assigns a smaller score to the first cow at which the two
sequences differ.
Each input contains \(T\) \((1 \leq T \leq 20)\) independent test cases. The sum of
\(N\) across all test cases is guaranteed to not exceed \(3 \cdot 10^5\).
Problem credits: Suhas Nagar
SCORING
- Input 3 satisfies \(N \leq 10\) and \(Q, C \leq 4\).
- Inputs 4-8 satisfy \(N \leq 1000\).
- Inputs 9-12 satisfy no additional constraints.
Problem credits: Suhas Nagar
The first line contains \(T\), the number of independent test cases. Each test
case is described as follows:
- First, a line containing \(N\), \(Q\), and \(C\).
- Next, a line containing the sequence \(c_1, \dots, c_N\) \((0 \leq c_i \leq C)\).
- Finally, \(Q\) lines each containing a pair \((a_j, h_j)\). It is guaranteed that all \(a_j\) within a test case are distinct.
For each test case, output a single line containing the lexicographically
smallest sequence of cowmpetency scores consistent with what Farmer John remembers, or \(-1\) if such a sequence does not
exist.
1
7 3 5
1 0 2 3 0 4 0
1 2
3 4
4 51 2 2 3 4 4 1We can see that the given output satisfies all of Farmer John's remembered
pairs.
- \(\max(c_1) = 1\), \(c_2 = 2\) and \(1<2\) so the first pair is satisfied
- \(\max(c_1,c_2,c_3) = 2\), \(c_4 = 3\) and \(2<3\) so the second pair is satisfied
- \(\max(c_1,c_2,c_3,c_4) = 3\), \(c_5 = 4\) and \(3<4\) so the third pair is satisfied
There are several other sequences consistent with Farmer John's memory, such as
1 2 2 3 5 4 1
1 2 2 3 4 4 5
However, none of these are lexicographically smaller than the given output.
5
7 6 10
0 0 0 0 0 0 0
1 2
2 3
3 4
4 5
5 6
6 7
8 4 9
0 0 0 0 1 6 0 6
1 3
6 7
4 7
2 3
2 1 1
0 0
1 2
10 4 10
1 2 0 2 1 5 8 6 0 3
4 7
1 2
5 7
3 7
10 2 8
1 0 0 0 0 5 7 0 0 0
4 6
6 91 2 3 4 5 6 7
1 1 2 6 1 6 7 6
-1
1 2 5 2 1 5 8 6 1 3
-1In test case 3, since \(C=1\), the only potential sequence is
1 1
However, in this case, cow 2 does not have a greater score than cow 1, so we
cannot satisfy the condition.
In test case 5, \(a_1\) and \(h_1\) tell us that cow 6 is the first cow to have a
strictly greater score than cows 1 through 4. Therefore, the largest score for
cows 1 through 6 is that of cow 6: 5. Since cow 7 has a score of 7, cow 7 is
the first cow to have a greater score than cows 1 through 6. So, the second
statement that cow 9 is the first cow to have a greater score than cows 1
through 6 cannot be true.
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Cowmpetency
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Cowmpetency