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Chao Xu
  • Member for 10 years, 3 months
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37 votes
1 answer
2k views

Is it NP-hard to fill up bins with minimum moves?

28 votes
1 answer
724 views

Subset sum problem with many divisibility conditions

23 votes
2 answers
2k views

Collectively pay the bill problem

14 votes
1 answer
289 views

Are runtime bounds decidable for anything nontrivial?

14 votes
1 answer
6k views

Complexity of finding the pseudoinverse matrix

13 votes
1 answer
1k views

Use minimum number of swaps so each bin contains balls of the same color

10 votes
1 answer
642 views

A programming language that can only implement computable bijective functions?

10 votes
2 answers
369 views

Is the following extension of finite state automata studied?

8 votes
1 answer
576 views

Bit complexity of O(1) time range query in a $k$-ary array

8 votes
1 answer
162 views

Find minimum number 1's so the matrix consist of 1 connected region of 1's

8 votes
0 answers
582 views

Predecessor query where the insertion order is known

7 votes
1 answer
419 views

Maxima of diagonals in a column wise and row wise sorted matrix

6 votes
1 answer
255 views

Regular expression over a monoid

6 votes
0 answers
141 views

NP-hardness of a special traveling salesman problem

6 votes
3 answers
1k views

What is the bitwise xor of an interval?

6 votes
1 answer
241 views

Represent string as concatenations

5 votes
1 answer
291 views

Use complementary slackness to prove the LP formulation of max-flow only need polynomial number of path constraints

5 votes
0 answers
235 views

Find a permutation that maximize the minimum of $\frac{a_n}{a_{n-1}} + \frac{a_n}{a_{n+1}}$

5 votes
1 answer
272 views

Find interval sums with minimum number of operation

5 votes
1 answer
101 views

Rearrange a sequence of real numbers to satisfy polynomial inequalities

5 votes
2 answers
1k views

Search for minimum in an array of $k$ monotonic subarrays

4 votes
2 answers
2k views

Data structure for finding the sum of edge weights on a path

3 votes
1 answer
897 views

A framework to capture common variation of sequence alignments

2 votes
1 answer
163 views

Find a sequence of integer powers faster than the naive algorithm

2 votes
1 answer
102 views

Multicommodity circulation formulation

1 vote
1 answer
139 views

Surprising and basic data structures [closed]