Initial Problem

Start: l0
Program_Vars: X₀, X₁, X₂, X₃
Temp_Vars:
Locations: l0, l1, l2, l3, l4, l5, l6, l7, l8, l9
Transitions:
t₀: l0(X₀, X₁, X₂, X₃) → l2(X₀, X₁, X₂, X₃)
t₂: l1(X₀, X₁, X₂, X₃) → l3(X₀, X₁, X₂, X₃) :|: X₀ < 0
t₃: l1(X₀, X₁, X₂, X₃) → l3(X₀, X₁, X₂, X₃) :|: 0 < X₀
t₄: l1(X₀, X₁, X₂, X₃) → l4(X₀, X₁, X₂, X₃) :|: X₀ ≤ 0 ∧ 0 ≤ X₀
t₁: l2(X₀, X₁, X₂, X₃) → l1(X₃, X₁, X₂, X₃)
t₅: l3(X₀, X₁, X₂, X₃) → l5(X₀, X₁, X₂, X₃) :|: X₀ < 0
t₆: l3(X₀, X₁, X₂, X₃) → l7(X₀, X₁, X₂, X₃) :|: 0 ≤ X₀
t₁₃: l4(X₀, X₁, X₂, X₃) → l9(X₀, X₁, X₂, X₃)
t₈: l5(X₀, X₁, X₂, X₃) → l1(X₀+2, X₁, X₂, X₃) :|: 0 ≤ 2+X₀
t₇: l5(X₀, X₁, X₂, X₃) → l6(X₀, X₀+2, X₂, X₃) :|: X₀+2 < 0
t₉: l6(X₀, X₁, X₂, X₃) → l1(-X₁, X₁, X₂, X₃)
t₁₁: l7(X₀, X₁, X₂, X₃) → l1(X₀-2, X₁, X₂, X₃) :|: X₀ ≤ 2
t₁₀: l7(X₀, X₁, X₂, X₃) → l8(X₀, X₁, X₀-2, X₃) :|: 2 < X₀
t₁₂: l8(X₀, X₁, X₂, X₃) → l1(-X₂, X₁, X₂, X₃)

Preprocessing

Found invariant 1+X₁ ≤ 0 ∧ X₁ ≤ 2+X₀ ∧ 4+X₀+X₁ ≤ 0 ∧ 2+X₀ ≤ X₁ ∧ 3+X₀ ≤ 0 for location l6

Found invariant 0 ≤ X₀ for location l7

Found invariant 1+X₀ ≤ 0 for location l5

Found invariant 2+X₂ ≤ X₀ ∧ 1 ≤ X₂ ∧ 4 ≤ X₀+X₂ ∧ X₀ ≤ 2+X₂ ∧ 3 ≤ X₀ for location l8

Found invariant X₀ ≤ 0 ∧ 0 ≤ X₀ for location l4

Found invariant X₀ ≤ 0 ∧ 0 ≤ X₀ for location l9

Problem after Preprocessing

Start: l0
Program_Vars: X₀, X₁, X₂, X₃
Temp_Vars:
Locations: l0, l1, l2, l3, l4, l5, l6, l7, l8, l9
Transitions:
t₀: l0(X₀, X₁, X₂, X₃) → l2(X₀, X₁, X₂, X₃)
t₂: l1(X₀, X₁, X₂, X₃) → l3(X₀, X₁, X₂, X₃) :|: X₀ < 0
t₃: l1(X₀, X₁, X₂, X₃) → l3(X₀, X₁, X₂, X₃) :|: 0 < X₀
t₄: l1(X₀, X₁, X₂, X₃) → l4(X₀, X₁, X₂, X₃) :|: X₀ ≤ 0 ∧ 0 ≤ X₀
t₁: l2(X₀, X₁, X₂, X₃) → l1(X₃, X₁, X₂, X₃)
t₅: l3(X₀, X₁, X₂, X₃) → l5(X₀, X₁, X₂, X₃) :|: X₀ < 0
t₆: l3(X₀, X₁, X₂, X₃) → l7(X₀, X₁, X₂, X₃) :|: 0 ≤ X₀
t₁₃: l4(X₀, X₁, X₂, X₃) → l9(X₀, X₁, X₂, X₃) :|: X₀ ≤ 0 ∧ 0 ≤ X₀
t₈: l5(X₀, X₁, X₂, X₃) → l1(X₀+2, X₁, X₂, X₃) :|: 0 ≤ 2+X₀ ∧ 1+X₀ ≤ 0
t₇: l5(X₀, X₁, X₂, X₃) → l6(X₀, X₀+2, X₂, X₃) :|: X₀+2 < 0 ∧ 1+X₀ ≤ 0
t₉: l6(X₀, X₁, X₂, X₃) → l1(-X₁, X₁, X₂, X₃) :|: 1+X₁ ≤ 0 ∧ X₁ ≤ 2+X₀ ∧ 4+X₀+X₁ ≤ 0 ∧ 2+X₀ ≤ X₁ ∧ 3+X₀ ≤ 0
t₁₁: l7(X₀, X₁, X₂, X₃) → l1(X₀-2, X₁, X₂, X₃) :|: X₀ ≤ 2 ∧ 0 ≤ X₀
t₁₀: l7(X₀, X₁, X₂, X₃) → l8(X₀, X₁, X₀-2, X₃) :|: 2 < X₀ ∧ 0 ≤ X₀
t₁₂: l8(X₀, X₁, X₂, X₃) → l1(-X₂, X₁, X₂, X₃) :|: 2+X₂ ≤ X₀ ∧ 1 ≤ X₂ ∧ 4 ≤ X₀+X₂ ∧ X₀ ≤ 2+X₂ ∧ 3 ≤ X₀

Analysing control-flow refined program

Cut unsatisfiable transition t₁₈₁: n_l1___13→l4

Cut unsatisfiable transition t₁₈₂: n_l1___16→l4

Cut unsatisfiable transition t₁₈₄: n_l1___6→l4

Found invariant X₁+X₂ ≤ 2 ∧ X₀+X₂ ≤ 0 ∧ 3 ≤ X₂ ∧ 2 ≤ X₁+X₂ ∧ 4+X₁ ≤ X₂ ∧ 0 ≤ X₀+X₂ ∧ 6+X₀ ≤ X₂ ∧ 1+X₁ ≤ 0 ∧ X₁ ≤ 2+X₀ ∧ 4+X₀+X₁ ≤ 0 ∧ 2+X₀ ≤ X₁ ∧ 3+X₀ ≤ 0 for location n_l6___3

Found invariant X₀+X₂ ≤ 0 ∧ 1 ≤ X₂ ∧ 0 ≤ X₀+X₂ ∧ 2+X₀ ≤ X₂ ∧ 1+X₀ ≤ 0 for location n_l1___6

Found invariant X₃ ≤ 2+X₂ ∧ X₃ ≤ X₀ ∧ 3 ≤ X₃ ∧ 4 ≤ X₂+X₃ ∧ 2+X₂ ≤ X₃ ∧ 6 ≤ X₀+X₃ ∧ X₀ ≤ X₃ ∧ 2+X₂ ≤ X₀ ∧ 1 ≤ X₂ ∧ 4 ≤ X₀+X₂ ∧ X₀ ≤ 2+X₂ ∧ 3 ≤ X₀ for location n_l8___1

Found invariant 1+X₀ ≤ 0 ∧ 0 ≤ 1+X₀ for location n_l3___15

Found invariant 1+X₃ ≤ 0 ∧ X₃ ≤ X₀ ∧ 2+X₀+X₃ ≤ 0 ∧ X₀ ≤ X₃ ∧ 1+X₀ ≤ 0 for location n_l3___23

Found invariant X₀ ≤ 1 ∧ 1 ≤ X₀ for location n_l7___17

Found invariant X₀ ≤ 1 ∧ 0 ≤ X₀ for location n_l1___20

Found invariant X₀+X₂ ≤ 0 ∧ 1 ≤ X₂ ∧ 0 ≤ X₀+X₂ ∧ 2+X₀ ≤ X₂ ∧ 1+X₀ ≤ 0 for location n_l3___5

Found invariant 1+X₀ ≤ 0 ∧ 0 ≤ 1+X₀ for location n_l5___14

Found invariant 3+X₃ ≤ 0 ∧ 2+X₃ ≤ X₁ ∧ 4+X₁+X₃ ≤ 0 ∧ X₃ ≤ X₀ ∧ 6+X₀+X₃ ≤ 0 ∧ X₁ ≤ 2+X₃ ∧ X₀ ≤ X₃ ∧ 1+X₁ ≤ 0 ∧ X₁ ≤ 2+X₀ ∧ 4+X₀+X₁ ≤ 0 ∧ 2+X₀ ≤ X₁ ∧ 3+X₀ ≤ 0 for location n_l6___19

Found invariant X₀ ≤ 0 ∧ 0 ≤ 1+X₀ for location n_l1___10

Found invariant 1+X₁ ≤ 0 ∧ 2+X₁ ≤ X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ 1 ≤ X₀ for location n_l1___13

Found invariant 1+X₁ ≤ 0 ∧ 2+X₁ ≤ X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ 1 ≤ X₀ for location n_l3___12

Found invariant 1+X₃ ≤ 0 ∧ X₃ ≤ X₀ ∧ 2+X₀+X₃ ≤ 0 ∧ X₀ ≤ X₃ ∧ 1+X₀ ≤ 0 for location n_l5___21

Found invariant X₀+X₂ ≤ 0 ∧ 1 ≤ X₂ ∧ 0 ≤ X₀+X₂ ∧ 2+X₀ ≤ X₂ ∧ 1+X₀ ≤ 0 for location n_l5___4

Found invariant 1+X₀ ≤ 0 ∧ 0 ≤ 1+X₀ for location n_l3___8

Found invariant X₃ ≤ X₀ ∧ 1 ≤ X₃ ∧ 2 ≤ X₀+X₃ ∧ X₀ ≤ X₃ ∧ 1 ≤ X₀ for location n_l7___2

Found invariant 2+X₁+X₂ ≤ 0 ∧ 2+X₂ ≤ X₀ ∧ 1 ≤ X₂ ∧ 0 ≤ 2+X₁+X₂ ∧ 4+X₁ ≤ X₂ ∧ 4 ≤ X₀+X₂ ∧ X₀ ≤ 2+X₂ ∧ 3+X₁ ≤ 0 ∧ 6+X₁ ≤ X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ 3 ≤ X₀ for location n_l8___9

Found invariant 1+X₀ ≤ 0 ∧ 0 ≤ 1+X₀ for location n_l1___16

Found invariant X₃ ≤ X₀ ∧ 1 ≤ X₃ ∧ 2 ≤ X₀+X₃ ∧ X₀ ≤ X₃ ∧ 1 ≤ X₀ for location n_l3___22

Found invariant 1+X₀ ≤ 0 ∧ 0 ≤ 1+X₀ for location n_l5___7

Found invariant X₃ ≤ X₀ ∧ X₀ ≤ X₃ for location l1

Found invariant X₀ ≤ 0 ∧ 0 ≤ X₀ for location l4

Found invariant X₀ ≤ 0 ∧ 0 ≤ X₀ for location l9

Found invariant 1+X₁ ≤ 0 ∧ 2+X₁ ≤ X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ 1 ≤ X₀ for location n_l7___11

Found invariant X₀ ≤ 1 ∧ 1 ≤ X₀ for location n_l3___18

MPRF for transition t₁₃₀: n_l1___13(X₀, X₁, X₂, X₃) → n_l3___12(X₀, X₁, X₂, X₃) :|: 0 ≤ 2+X₀ ∧ 0 < X₀ ∧ 1 ≤ X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ 1 ≤ X₀ ∧ 0 < X₀ ∧ 1+X₁ ≤ 0 ∧ 2+X₁ ≤ X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ 1 ≤ X₀ of depth 1:

new bound:

2⋅X₃+2 {O(n)}

MPRF:

n_l3___12 [X₀-2 ]
n_l3___5 [-X₀ ]
n_l5___4 [X₂ ]
n_l6___3 [-X₀ ]
n_l1___13 [X₀+2 ]
n_l7___11 [-X₁-2 ]
n_l8___9 [-X₁-2 ]
n_l1___6 [-X₀ ]

MPRF for transition t₁₃₅: n_l1___6(X₀, X₁, X₂, X₃) → n_l3___5(X₀, X₁, X₂, X₃) :|: 1+X₀ ≤ 0 ∧ X₀ < 0 ∧ X₀ ≤ 2 ∧ 1+X₀ ≤ 0 ∧ X₀+X₂ ≤ 0 ∧ 0 ≤ X₀+X₂ ∧ 1+X₀ ≤ 0 ∧ X₀ < 0 ∧ X₀+X₂ ≤ 0 ∧ 1 ≤ X₂ ∧ 0 ≤ X₀+X₂ ∧ 2+X₀ ≤ X₂ ∧ 1+X₀ ≤ 0 of depth 1:

new bound:

6⋅X₃+2 {O(n)}

MPRF:

n_l3___12 [2⋅X₀+2 ]
n_l3___5 [2⋅X₂-2 ]
n_l5___4 [2⋅X₂-2 ]
n_l6___3 [-2⋅X₀-2 ]
n_l1___13 [2-2⋅X₁ ]
n_l7___11 [2-2⋅X₁ ]
n_l8___9 [3⋅X₀-X₂ ]
n_l1___6 [-3⋅X₀-X₂ ]

MPRF for transition t₁₃₆: n_l3___12(X₀, X₁, X₂, X₃) → n_l7___11(X₀, X₁, X₂, X₃) :|: 1 ≤ X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ 0 ≤ X₀ ∧ 1+X₁ ≤ 0 ∧ 2+X₁ ≤ X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ 1 ≤ X₀ of depth 1:

new bound:

2⋅X₃+2 {O(n)}

MPRF:

n_l3___12 [X₀+1 ]
n_l3___5 [-X₀-1 ]
n_l5___4 [X₂-1 ]
n_l6___3 [X₂-1 ]
n_l1___13 [1-X₁ ]
n_l7___11 [X₀-3 ]
n_l8___9 [X₀-3 ]
n_l1___6 [-X₀-1 ]

MPRF for transition t₁₄₁: n_l3___5(X₀, X₁, X₂, X₃) → n_l5___4(X₀, X₁, X₂, X₃) :|: 1+X₀ ≤ 0 ∧ X₀+X₂ ≤ 0 ∧ 0 ≤ X₀+X₂ ∧ X₀ < 0 ∧ X₀+X₂ ≤ 0 ∧ 1 ≤ X₂ ∧ 0 ≤ X₀+X₂ ∧ 2+X₀ ≤ X₂ ∧ 1+X₀ ≤ 0 of depth 1:

new bound:

2⋅X₃+2 {O(n)}

MPRF:

n_l3___12 [X₀-2 ]
n_l3___5 [X₂ ]
n_l5___4 [-X₀-4 ]
n_l6___3 [-X₀-4 ]
n_l1___13 [-X₁-2 ]
n_l7___11 [X₀-2 ]
n_l8___9 [X₀-2 ]
n_l1___6 [X₂ ]

MPRF for transition t₁₄₇: n_l5___4(X₀, X₁, X₂, X₃) → n_l6___3(X₀, X₀+2, X₂, X₃) :|: 1+X₀ ≤ 0 ∧ X₀+X₂ ≤ 0 ∧ 0 ≤ X₀+X₂ ∧ 2+X₀ < 0 ∧ X₀+X₂ ≤ 0 ∧ 1 ≤ X₂ ∧ 0 ≤ X₀+X₂ ∧ 2+X₀ ≤ X₂ ∧ 1+X₀ ≤ 0 of depth 1:

new bound:

2⋅X₃+2 {O(n)}

MPRF:

n_l3___12 [-X₁ ]
n_l3___5 [X₂+2 ]
n_l5___4 [X₂-1 ]
n_l6___3 [-X₀-2 ]
n_l1___13 [X₀ ]
n_l7___11 [-X₁ ]
n_l8___9 [X₀ ]
n_l1___6 [2-X₀ ]

MPRF for transition t₁₅₀: n_l6___3(X₀, X₁, X₂, X₃) → n_l1___13(-X₀-2, X₀+2, X₂, X₃) :|: 2 < X₂ ∧ X₀+X₂ ≤ 0 ∧ 0 ≤ X₀+X₂ ∧ X₁+X₂ ≤ 2 ∧ 2 ≤ X₁+X₂ ∧ 3+X₀ ≤ 0 ∧ X₀+2 ≤ X₁ ∧ X₁ ≤ 2+X₀ ∧ X₁+X₂ ≤ 2 ∧ X₀+X₂ ≤ 0 ∧ 3 ≤ X₂ ∧ 2 ≤ X₁+X₂ ∧ 4+X₁ ≤ X₂ ∧ 0 ≤ X₀+X₂ ∧ 6+X₀ ≤ X₂ ∧ 1+X₁ ≤ 0 ∧ X₁ ≤ 2+X₀ ∧ 4+X₀+X₁ ≤ 0 ∧ 2+X₀ ≤ X₁ ∧ 3+X₀ ≤ 0 of depth 1:

new bound:

2⋅X₃ {O(n)}

MPRF:

n_l3___12 [-X₁ ]
n_l3___5 [X₂ ]
n_l5___4 [-X₀ ]
n_l6___3 [1-X₁ ]
n_l1___13 [X₀ ]
n_l7___11 [-X₁ ]
n_l8___9 [-X₁ ]
n_l1___6 [X₂ ]

MPRF for transition t₁₅₂: n_l7___11(X₀, X₁, X₂, X₃) → n_l8___9(X₀, X₁, X₀-2, X₃) :|: 1 ≤ X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ 2 < X₀ ∧ 1+X₁ ≤ 0 ∧ 2+X₁ ≤ X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ 1 ≤ X₀ of depth 1:

new bound:

2⋅X₃+4 {O(n)}

MPRF:

n_l3___12 [X₀+3 ]
n_l3___5 [1-X₀ ]
n_l5___4 [1-X₀ ]
n_l6___3 [X₂+1 ]
n_l1___13 [X₀+3 ]
n_l7___11 [X₀+3 ]
n_l8___9 [-X₁-1 ]
n_l1___6 [1-X₀ ]

MPRF for transition t₁₅₇: n_l8___9(X₀, X₁, X₂, X₃) → n_l1___6(2-X₀, X₁, X₀-2, X₃) :|: 2 < X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ X₀ ≤ X₂+2 ∧ 2+X₂ ≤ X₀ ∧ 3 ≤ X₀ ∧ X₀ ≤ X₂+2 ∧ 2+X₂ ≤ X₀ ∧ 2+X₁+X₂ ≤ 0 ∧ 2+X₂ ≤ X₀ ∧ 1 ≤ X₂ ∧ 0 ≤ 2+X₁+X₂ ∧ 4+X₁ ≤ X₂ ∧ 4 ≤ X₀+X₂ ∧ X₀ ≤ 2+X₂ ∧ 3+X₁ ≤ 0 ∧ 6+X₁ ≤ X₀ ∧ X₀+X₁ ≤ 0 ∧ 0 ≤ X₀+X₁ ∧ 3 ≤ X₀ of depth 1:

new bound:

2⋅X₃+6 {O(n)}

MPRF:

n_l3___12 [X₀-2 ]
n_l3___5 [X₂-4 ]
n_l5___4 [-X₀-4 ]
n_l6___3 [X₂-4 ]
n_l1___13 [-X₁-2 ]
n_l7___11 [-X₁-2 ]
n_l8___9 [X₀-2 ]
n_l1___6 [-X₀-4 ]

CFR did not improve the program. Rolling back

All Bounds

Timebounds

Overall timebound:inf {Infinity}
t₀: 1 {O(1)}
t₂: inf {Infinity}
t₃: inf {Infinity}
t₄: 1 {O(1)}
t₁: 1 {O(1)}
t₅: inf {Infinity}
t₆: inf {Infinity}
t₁₃: 1 {O(1)}
t₇: inf {Infinity}
t₈: inf {Infinity}
t₉: inf {Infinity}
t₁₀: inf {Infinity}
t₁₁: inf {Infinity}
t₁₂: inf {Infinity}

Costbounds

Overall costbound: inf {Infinity}
t₀: 1 {O(1)}
t₂: inf {Infinity}
t₃: inf {Infinity}
t₄: 1 {O(1)}
t₁: 1 {O(1)}
t₅: inf {Infinity}
t₆: inf {Infinity}
t₁₃: 1 {O(1)}
t₇: inf {Infinity}
t₈: inf {Infinity}
t₉: inf {Infinity}
t₁₀: inf {Infinity}
t₁₁: inf {Infinity}
t₁₂: inf {Infinity}

Sizebounds

t₀, X₀: X₀ {O(n)}
t₀, X₁: X₁ {O(n)}
t₀, X₂: X₂ {O(n)}
t₀, X₃: X₃ {O(n)}
t₂, X₀: 2⋅X₃+3 {O(n)}
t₂, X₁: 2⋅X₁+2⋅X₃+3 {O(n)}
t₂, X₂: 2⋅X₂+2⋅X₃+3 {O(n)}
t₂, X₃: 2⋅X₃ {O(n)}
t₃, X₀: 2⋅X₃+3 {O(n)}
t₃, X₁: 2⋅X₁+2⋅X₃+3 {O(n)}
t₃, X₂: 2⋅X₂+2⋅X₃+3 {O(n)}
t₃, X₃: 2⋅X₃ {O(n)}
t₄, X₀: 0 {O(1)}
t₄, X₁: 4⋅X₃+5⋅X₁+6 {O(n)}
t₄, X₂: 4⋅X₃+5⋅X₂+6 {O(n)}
t₄, X₃: 5⋅X₃ {O(n)}
t₁, X₀: X₃ {O(n)}
t₁, X₁: X₁ {O(n)}
t₁, X₂: X₂ {O(n)}
t₁, X₃: X₃ {O(n)}
t₅, X₀: 2⋅X₃+3 {O(n)}
t₅, X₁: 2⋅X₁+2⋅X₃+3 {O(n)}
t₅, X₂: 2⋅X₂+2⋅X₃+3 {O(n)}
t₅, X₃: 2⋅X₃ {O(n)}
t₆, X₀: 2⋅X₃+3 {O(n)}
t₆, X₁: 2⋅X₁+2⋅X₃+3 {O(n)}
t₆, X₂: 2⋅X₂+2⋅X₃+3 {O(n)}
t₆, X₃: 2⋅X₃ {O(n)}
t₁₃, X₀: 0 {O(1)}
t₁₃, X₁: 4⋅X₃+5⋅X₁+6 {O(n)}
t₁₃, X₂: 4⋅X₃+5⋅X₂+6 {O(n)}
t₁₃, X₃: 5⋅X₃ {O(n)}
t₇, X₀: 2⋅X₃+3 {O(n)}
t₇, X₁: 2⋅X₃+3 {O(n)}
t₇, X₂: 2⋅X₂+2⋅X₃+3 {O(n)}
t₇, X₃: 2⋅X₃ {O(n)}
t₈, X₀: 1 {O(1)}
t₈, X₁: 2⋅X₁+2⋅X₃+3 {O(n)}
t₈, X₂: 2⋅X₂+2⋅X₃+3 {O(n)}
t₈, X₃: 2⋅X₃ {O(n)}
t₉, X₀: 2⋅X₃+3 {O(n)}
t₉, X₁: 2⋅X₃+3 {O(n)}
t₉, X₂: 2⋅X₂+2⋅X₃+3 {O(n)}
t₉, X₃: 2⋅X₃ {O(n)}
t₁₀, X₀: 2⋅X₃+3 {O(n)}
t₁₀, X₁: 2⋅X₁+2⋅X₃+3 {O(n)}
t₁₀, X₂: 2⋅X₃+3 {O(n)}
t₁₀, X₃: 2⋅X₃ {O(n)}
t₁₁, X₀: 2 {O(1)}
t₁₁, X₁: 2⋅X₁+2⋅X₃+3 {O(n)}
t₁₁, X₂: 2⋅X₂+2⋅X₃+3 {O(n)}
t₁₁, X₃: 2⋅X₃ {O(n)}
t₁₂, X₀: 2⋅X₃+3 {O(n)}
t₁₂, X₁: 2⋅X₁+2⋅X₃+3 {O(n)}
t₁₂, X₂: 2⋅X₃+3 {O(n)}
t₁₂, X₃: 2⋅X₃ {O(n)}