CODE FESTIVAL 2015 予選A 解説

1. 5
0
0+ 12. /

2. 2
• E F Lh “ 1 O ih
• j E F O r
•
– E 0+ 12. / F E 0+ 12. / F

3. 51
• “ 1 j s s h
• “ 1 a a “j D C Oh
• O “ 1 j r r h
• ok
– sr at
• Tc c
• aʼ’ j ʻ‘ V S T
– 5 : A 5 5A A 5 : 4
– “ a Ot
• Tc c
• I “ _̲ a p n V S T
• Lh ataʼ’ j ʻ‘ had Ve

4. =A BD
21
,3-‐‑‒ 5 0 +1 +

5. =A
• 2 + E
• 5 2 D
• [
5 + 5 L 5 VO A
VCD D
• 2 5 VT C AV ]
• VT C A P
•
– 2
– +
– E[ E C

6. B
• = O
•
N D

7. B
• [
= O V Pi
• -‐‑‒
– D -‐‑‒ E O
• +-‐‑‒ -‐‑‒ *
–
• 5 + 5 L 5 VO A
• 5 [ -‐‑‒ 9 5 [
-‐‑‒ 9 + -‐‑‒ 9 V O
–
• +-‐‑‒ +-‐‑‒ -‐‑‒
• L ~∼ 2 SCT NTCIV -‐‑‒ 29 E
V O
– -‐‑‒ 9 VNTFIV V L O

8. -‐‑‒ 450 1

9. • 2 E 9 9i T 9
L T N I ETF
• S 5 N F9 T
V V V D
• N I E V N
•
– 2
– 5
–

10. •
– i T O E 5 V
•
– L O V 9
i T L
•
– E 9 E 5 BV T S
– N O F9 O i TTF
– 9<2 O =E B V
•
– < = S
• S D S

11. •
– B LI L
– I F95 V V L
– < L=D <i T = BO F 9DD
E – L
• B
•
– E < L=D <i T = BS
– DD E 5 BV A B BO F9
BO i TTF
• DD 9 SCF9 BO
F 9 S
– <2 BO =E B V

12. 1923 3<=5 0 ) (+ 0

13. • [
• r ND r D
• rR SmR
S[
• R S rT
• R S r r o
• o]m T [ ag
o l rO
•
– ( V V ( ,
– ( V V ( + j V

14. •
– ( V V V (
•
– [ j
• r r o lN g r
• r o lN r D x o mo
• i ND [ N D x o
– j
• D D A m ag N
Xo X [
• j N r D ) ) mo

15. •
– 2 DA EA D ll E l
MMMMMm
– X
•
– 9 )
DP[][]% %INF%l %
DP[0][0]%=%0%
for%(i%:%1...M)%for%(j%:%0...X[i]71)%
%%for%(k%:%X[i]...N)%
%%%%L%=%X[i]7j%
%%%%R%=%k7X[i]%
%%%%T%=%min(L*2+R,%L+R*2)%
%%%%DP[i][k]%=%min(DP[i][k],%max(DP[i71][j],%T))%

16. •
– V +
•
–
• = m[l l
–
• ( R l l S
a N l l l
– D [R l l S
• 2 DA D [R l l SNm
• DA L 2 D (A L (Nm
• D ) ) -‐‑‒ = mo m
• mN2 DA DA mo

17. •
– V +
•
–
• = m[l l
• – r * ) n
– (lN [ Xo [
–
• ( R l l S
a N l l l

18. •
– D [R l l S
• 2 DA D [R l l SNm
• DA L 2 D (A L (Nm
• D ) ) -‐‑‒ = jN DA -‐‑‒ D (A g X
o m
– D (A D [ ro
• mN2 DA DA mo
–
• ( j a N
• R( j a S r l P
la o
– [ DA ma – mro g
•
– 9 FIC

19. •
– [ i
– l
•
– 9 FIC)

20. • ] m l
– = ) = ) m m l
•
– 9 FIC