Perfect Half Space Games Thomas Colcombet, Marcin Jurdzi nski, - - PowerPoint PPT Presentation

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Perfect Half Space Games Thomas Colcombet, Marcin Jurdzi nski, - - PowerPoint PPT Presentation

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games Perfect Half Space Games Thomas Colcombet, Marcin Jurdzi nski, Ranko Lazi c, and Sylvain Schmitz LSV, ENS Paris-Saclay & CNRS & Inria LICS 2017,


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SLIDE 1

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Perfect Half Space Games

Thomas Colcombet, Marcin Jurdzi´ nski, Ranko Lazi´ c, and Sylvain Schmitz LSV, ENS Paris-Saclay & CNRS & Inria LICS 2017, June 23rd, 2017

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SLIDE 2

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

What to do this week-end?

Reykjavik Landmannalaugar Th´

  • rsm¨
  • rk

Hr´ utafj¨

  • rdur

Vatnaj¨

  • kull

M´ yvatn

6o 4o 10o 9o 13o 12o 2 1 1

R L T H V M

Maximal dry temperature as a parity objective Uncontrolled events Uncontrolled events as a two-players game 2 1 1 Discrete resources Discrete resources as a multi-energy objective

(−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0) 2/10

slide-3
SLIDE 3

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

What to do this week-end?

Reykjavik Landmannalaugar Th´

  • rsm¨
  • rk

Hr´ utafj¨

  • rdur

Vatnaj¨

  • kull

M´ yvatn

6o 4o 10o 9o 13o 12o 2 1 1

R L T H V M

Maximal dry temperature as a parity objective Uncontrolled events Uncontrolled events as a two-players game 2 1 1 Discrete resources Discrete resources as a multi-energy objective

(−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0) 2/10

slide-4
SLIDE 4

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

What to do this week-end?

Reykjavik Landmannalaugar Th´

  • rsm¨
  • rk

Hr´ utafj¨

  • rdur

Vatnaj¨

  • kull

M´ yvatn

6o 4o 10o 9o 13o 12o 2 1 1

R L T H V M

Maximal dry temperature as a parity objective Uncontrolled events Uncontrolled events as a two-players game 2 1 1 Discrete resources Discrete resources as a multi-energy objective

(−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0) 2/10

slide-5
SLIDE 5

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

What to do this week-end?

Reykjavik Landmannalaugar Th´

  • rsm¨
  • rk

Hr´ utafj¨

  • rdur

Vatnaj¨

  • kull

M´ yvatn

6o 4o 10o 9o 13o 12o 2 1 1

R L T H V M

Maximal dry temperature as a parity objective Uncontrolled events Uncontrolled events as a two-players game 2 1 1 Discrete resources Discrete resources as a multi-energy objective

(−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0) 2/10

slide-6
SLIDE 6

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

What to do this week-end?

Reykjavik Landmannalaugar Th´

  • rsm¨
  • rk

Hr´ utafj¨

  • rdur

Vatnaj¨

  • kull

M´ yvatn

6o 4o 10o 9o 13o 12o 2 1 1

R L T H V M

Maximal dry temperature as a parity objective Uncontrolled events Uncontrolled events as a two-players game 2 1 1 Discrete resources Discrete resources as a multi-energy objective

(−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0) 2/10

slide-7
SLIDE 7

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

What to do this week-end?

Reykjavik Landmannalaugar Th´

  • rsm¨
  • rk

Hr´ utafj¨

  • rdur

Vatnaj¨

  • kull

M´ yvatn

6o 4o 10o 9o 13o 12o 2 1 1

R L T H V M

Maximal dry temperature as a parity objective Uncontrolled events Uncontrolled events as a two-players game 2 1 1 Discrete resources Discrete resources as a multi-energy objective

(−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0) 2/10

slide-8
SLIDE 8

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

What to do this week-end?

Reykjavik Landmannalaugar Th´

  • rsm¨
  • rk

Hr´ utafj¨

  • rdur

Vatnaj¨

  • kull

M´ yvatn

6o 4o 10o 9o 13o 12o 2 1 1

R L T H V M

Maximal dry temperature as a parity objective Uncontrolled events Uncontrolled events as a two-players game 2 1 1 Discrete resources Discrete resources as a multi-energy objective

(−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0) 2/10

slide-9
SLIDE 9

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

What to do this week-end?

Reykjavik Landmannalaugar Th´

  • rsm¨
  • rk

Hr´ utafj¨

  • rdur

Vatnaj¨

  • kull

M´ yvatn

6o 4o 10o 9o 13o 12o 2 1 1

R L T H V M

Maximal dry temperature as a parity objective Uncontrolled events Uncontrolled events as a two-players game 2 1 1 Discrete resources Discrete resources as a multi-energy objective

(−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0) 2/10

slide-10
SLIDE 10

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

What to do this week-end?

Reykjavik Landmannalaugar Th´

  • rsm¨
  • rk

Hr´ utafj¨

  • rdur

Vatnaj¨

  • kull

M´ yvatn

6o 4o 10o 9o 13o 12o 2 1 1

R L T H V M

Maximal dry temperature as a parity objective Uncontrolled events Uncontrolled events as a two-players game 2 1 1 Discrete resources Discrete resources as a multi-energy objective

(−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0) 2/10

slide-11
SLIDE 11

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

What to do this week-end?

Reykjavik Landmannalaugar Th´

  • rsm¨
  • rk

Hr´ utafj¨

  • rdur

Vatnaj¨

  • kull

M´ yvatn

6o 4o 10o 9o 13o 12o 2 1 1

R L T H V M

Maximal dry temperature as a parity objective Uncontrolled events Uncontrolled events as a two-players game 2 1 1 Discrete resources Discrete resources as a multi-energy objective

(−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0) 2/10

slide-12
SLIDE 12

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

What to do this week-end?

Reykjavik Landmannalaugar Th´

  • rsm¨
  • rk

Hr´ utafj¨

  • rdur

Vatnaj¨

  • kull

M´ yvatn

6o 4o 10o 9o 13o 12o 2 1 1

R L T H V M

Maximal dry temperature as a parity objective Uncontrolled events Uncontrolled events as a two-players game 2 1 1 Discrete resources Discrete resources as a multi-energy objective

(−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0) 2/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Multi-Dimensional Energy Parity Games

Player 1 wins a play if both

◮ energy objective: no

component goes negative

◮ parity objective: the maximal

priority is odd

2 1 1

R L T H V M (−1,0) (−4,−3) (0,0) (−1,0) (0,0) (−1,0) (−2,−1) (−4,−5) (−1,0) (−1,0) (1,0)

Example

R(0,0)

(1,0)

− − − → R(1,0)

(1,0)

− − − → R(2,0)

(−1,0)

− − − − → H(1,0)

(0,0)

− − − → R(1,0) → ···

3/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Multi-Dimensional Energy Parity Games

Applications

◮ contractive (⊕,!)-Horn linear logic

(Kanovich, APAL ’95)

◮ (weak) simulation of finite-state systems by Petri nets

(Abdulla et al., Concur ’13)

◮ model-checking Petri nets with a fragment of µ-calculus

(Abdulla et al., Concur ’13)

◮ resource-bounded agent temporal logic RB±ATL∗

(Alechina et al., RP ’16 & AI ’17)

3/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Multi-Dimensional Energy Parity Games

Complexity lower bound upper bound

  • w. initial credit

∃ initial credit

3/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Multi-Dimensional Energy Parity Games

Complexity lower bound upper bound

  • w. initial credit

EXPSPACE TOWER

(Lasota, IPL ’09) (Br´ azdil et al., ICALP ’10)

∃ initial credit

coNP coNP

(Chatterjee et al., FSTTCS ’10) (Chatterjee et al., FSTTCS ’10) 3/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Multi-Dimensional Energy Parity Games

Complexity lower bound upper bound

  • w. initial credit

2-EXP TOWER

(Courtois and S., MFCS ’14) (Br´ azdil et al., ICALP ’10)

∃ initial credit

coNP coNP

(Chatterjee et al., FSTTCS ’10) (Chatterjee et al., FSTTCS ’10) 3/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Multi-Dimensional Energy Parity Games

Complexity lower bound upper bound

  • w. initial credit

2-EXP 2-EXP

(Courtois and S., MFCS ’14) (Jurdzi´ nski et al., ICALP ’15)

∃ initial credit

coNP coNP

(Chatterjee et al., FSTTCS ’10) (Chatterjee et al., FSTTCS ’10) 3/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Multi-Dimensional Energy Parity Games

Complexity lower bound upper bound

  • w. initial credit

2-EXP

(Courtois and S., MFCS ’14)

∃ initial credit

coNP coNP

(Chatterjee et al., Concur ’12) (Chatterjee et al., Concur ’12) 3/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Multi-Dimensional Energy Parity Games

Complexity lower bound upper bound

  • w. initial credit

2-EXP

decidable

(Courtois and S., MFCS ’14) (Abdulla et al., Concur ’13)

∃ initial credit

coNP coNP

(Chatterjee et al., Concur ’12) (Chatterjee et al., Concur ’12) 3/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Multi-Dimensional Energy Parity Games

Complexity lower bound upper bound

  • w. initial credit

2-EXP TOWER

(Courtois and S., MFCS ’14) (Janˇ car, RP ’15)

∃ initial credit

coNP coNP

(Chatterjee et al., Concur ’12) (Chatterjee et al., Concur ’12) 3/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Multi-Dimensional Energy Parity Games

Complexity lower bound upper bound

  • w. initial credit

2-EXP 2-EXP

(Courtois and S., MFCS ’14) this talk

∃ initial credit

coNP coNP

(Chatterjee et al., Concur ’12) (Chatterjee et al., Concur ’12) 3/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Fixed Dimensional Energy Fixed Parity Games

Complexity lower bound upper bound

  • w. initial credit

EXP for d 4

pseudoP

(Courtois and S., MFCS ’14) this talk

∃ initial credit pseudoP

this talk 3/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Outline

multi-dimensional energy parity games extended multi-dimensional energy games (Br´ azdil et al., ICALP ’10) bounding games (Jurdzi´ nski et al., ICALP ’15) perfect half space games (this paper) lexicographic energy games (Colcombet and Niwi´ nski) mean-payoff games (Comin and Rizzi, Algorithmica ’16)

(Janˇ car, RP ’15)

4/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Extended Multi-Dimensional Energy Games

Encode Priorities as Energy (Janˇ

car, RP ’15)

Two new dimensions: tolerance to humid low/high temperature 2 1 1

R L T H V M (−1,0,−1,−1) (−4,−3,ω,0) (0,0,−1,0) (−1,0,ω,0) (0,0,−1,0) (−1,0,ω,0) (−2,−1,−1,0) (−4,−5,−1,−1) (−1,0,−1,0) (−1,0,−1,0) (1,0,−1,0) 5/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Bounding Games

Player 1’s Objective

energy ∃ bounding ∃

6/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Bounding Games

Player 1’s Objective

energy ∃ bounding ∃

6/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Bounding Games

Player 1’s Objective

energy ∃ bounding ∃

6/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Bounding Games

Player 1’s Objective

energy ∃ bounding ∃

6/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Bounding Games

Player 1’s Objective

energy ∃ bounding ∃

6/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Bounding Games

Encoding Extended Energy Games

Bin excess energy

  • (...,−1,...)

Unbounded replenishing

(...,ω,...)

  • (...,0,...)

(0,1,0) (0)

6/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Bounding Games

Theorem (Jurdzi´

nski et al., ICALP ’15)

Bounding games on multi-weighted game graphs (V,E,d) are solvable in (|V| · E)O(d4). Corollary The given initial credit problem with credit c for energy parity games on multi-weighted game graphs (V,E,d) with p even priorities is solvable in O(|V| · E)2O(dlog(d+p)) + O(d · logc) .

6/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Bounding Games

Theorem (Jurdzi´

nski et al., ICALP ’15)

Bounding games on multi-weighted game graphs (V,E,d) are solvable in (|V| · E)O(d4). Corollary The given initial credit problem with credit c for energy parity games on multi-weighted game graphs (V,E,d) with p even priorities is solvable in O(|V| · E)2O(dlog(d+p)) + O(d · logc) .

6/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Bounding Games

Theorem (this paper) Bounding games on multi-weighted game graphs (V,E,d) are solvable in (|V| · E)O(d3). Corollary The given initial credit problem with credit c for energy parity games on multi-weighted game graphs (V,E,d) with p even priorities is solvable in O(|V| · E)2O(dlog(d+p)) + O(d · logc) .

6/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Perfect Half Space Games

Player 2’s Objective in a Bounding Game

Key Intuition Player 2 can escape in a perfect half space

7/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Perfect Half Space Games

Player 2’s Objective in a Bounding Game

Key Intuition Player 2 can escape in a perfect half space

7/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Perfect Half Space Games

Perfect Half Space {(x,y) : x + y < 0}

7/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Perfect Half Space Games

Perfect Half Space {(x,y) : x + y < 0} boundary: {(x,y) : x + y = 0}

7/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Perfect Half Space Games

Perfect Half Space {(x,y) : x + y < 0} ∪ {(x,y) : x + y = 0 ∧ x < 0}

7/10

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SLIDE 40

Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Perfect Half Space Games

vL vR

(0,0) (−1,0) (0,0) (0,−1) (1,−1) (0,0) (−1,1) (0,0)

Plays

◮ pairs of vertices and perfect half spaces:

(v0,H0)

w1

− − → (v1,H1)

w2

− − → (v2,H2)···

◮ in his vertices, Player 2 chooses the current perfect half

space

◮ Player 2 wins if ∃i s.t.

j0 wj diverges into j>i Hj

7/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Perfect Half Space Games

vL vR

(0,0) (−1,0) (0,0) (0,−1) (1,−1) (0,0) (−1,1) (0,0)

◮ Player 2 wins if ∃i s.t.

j0 wj diverges into j>i Hj

Example

HL

HR

=

7/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Solving Perfect Half Space Games

Theorem Perfect half space games on multi-weighted game graphs (V,E,d) are solvable in (|V| · E)O(d3). Proof Idea

◮ reduce to a lexicographic energy game (Colcombet and

Niwi´ nski)

◮ ≈ perfect half space game with a single fixed H ◮ itself reduced to a mean-payoff game

8/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Solving Perfect Half Space Games

Theorem Perfect half space games on multi-weighted game graphs (V,E,d) are solvable in (|V| · E)O(d3). Proof Idea

◮ reduce to a lexicographic energy game (Colcombet and

Niwi´ nski)

◮ ≈ perfect half space game with a single fixed H ◮ itself reduced to a mean-payoff game

8/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Player 2 Strategies

Oblivious Strategy Player 2 chooses the same Hv every time it visits vertex v Theorem If Player 2 has a winning strategy in a perfect half space game, then it has an oblivious one. “Counterless” Strategy Corollary (Br´

azdil et al., ICALP ’10)

If Player 2 has a winning strategy in a multi-dimensional energy parity game, then it has a positional one.

9/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Player 2 Strategies

Oblivious Strategy Player 2 chooses the same Hv every time it visits vertex v Theorem If Player 2 has a winning strategy in a perfect half space game, then it has an oblivious one. “Counterless” Strategy Corollary (Br´

azdil et al., ICALP ’10)

If Player 2 has a winning strategy in a multi-dimensional energy parity game, then it has a positional one.

9/10

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Energy Parity Games Extended Energy Games Bounding Games Perfect Half Space Games

Concluding Remarks

◮ tight 2-EXP bounds for multi-energy parity games ◮ impacts numerous problems ◮ fine understanding of Player 2’s strategies:

Player 2 can win by announcing in which perfect half space he will escape

10/10

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SLIDE 47

Disclaimer References

Disclaimer

The Icelandic Met Office does not endorse any of the information provided during this talk, and cannot be held liable for a ruined week-end subsequent to foolishly trusting these fabricated forecasts.

11/10

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Disclaimer References

References

Abdulla, P .A., Mayr, R., Sangnier, A., and Sproston, J., 2013. Solving parity games on integer vectors. In Concur 2013, volume 8052 of LNCS, pages 106–120. Springer. doi:10.1007/978-3-642-40184-8 9. Alechina, N., Bulling, N., Demri, S., and Logan, B., 2016. On the complexity of resource-bounded logics. In RP 2016, volume 9899 of LNCS, pages 36–50. Springer. doi:10.1007/978-3-319-45994-3 3. Alechina, N., Bulling, N., Logan, B., and Nguyen, H.N., 2017. The virtues of idleness: A decidable fragment of resource agent logic. Artif. Intell. doi:10.1016/j.artint.2016.12.005. to appear. Br´ azdil, T., Janˇ car, P ., and Kuˇ cera, A., 2010. Reachability games on extended vector addition systems with states. In ICALP 2010, volume 6199 of LNCS, pages 478–489. Springer. doi:10.1007/978-3-642-14162-1 40. arXiv version available from http://arxiv.org/abs/1002.2557. Chatterjee, K., Randour, M., and Raskin, J.F ., 2014. Strategy synthesis for multi-dimensional quantitative objectives. Acta Inf., 51(3–4):129–163. doi:10.1007/s00236-013-0182-6. Colcombet, T. and Niwi´ nski, D., 2017. Lexicographic energy games. Manuscript. Comin, C. and Rizzi, R., 2016. Improved pseudo-polynomial bound for the value problem and optimal strategy synthesis in mean payoff games. Algorithmica. doi:10.1007/s00453-016-0123-1. To appear. Jurdzi´ nski, M., Lazi´ c, R., and Schmitz, S., 2015. Fixed-dimensional energy games are in pseudo-polynomial time. In ICALP 2015, volume 9135 of LNCS, pages 260–272. Springer. doi:10.1007/978-3-662-47666-6 21. arXiv version available from https://arxiv.org/abs/1502.06875. Kanovich, M.I., 1995. Petri nets, Horn programs, linear logic and vector games. Ann. Pure App. Logic, 75(1–2): 107–135. doi:10.1016/0168-0072(94)00060-G. Lasota, S., 2009. EXPSPACE lower bounds for the simulation preorder between a communication-free Petri net and a finite-state system. Information Processing Letters, 109(15):850–855. doi:10.1016/j.ipl.2009.04.003. Velner, Y., Chatterjee, K., Doyen, L., Henzinger, T.A., Rabinovich, A., and Raskin, J.F ., 2015. The complexity of multi-mean-payoff and multi-energy games. Inform. and Comput., 241:177–196. doi:10.1016/j.ic.2015.03.001. Zwick, U. and Paterson, M., 1996. The complexity of mean payoff games on graphs. Theor. Comput. Sci., 158(1): 343–359. doi:10.1016/0304-3975(95)00188-3. 12/10