WPC4F - Through the troops

Having crossed the first hurdle, Mario encounters a long and narrow alleyway, with turtles. Mario can cross it by jumping from one turtle to another. Whenever Mario makes his jump on any given turtle, he can leave it in any of the three possible states, as per his choice. These states are:

  • Active (A)
  • Dormant (D)
  • Bruised (B)

There are n turtles in the street, indexed 0..(n-1). Each jump costs some amount of energy, which depends on the index of turtle as well as the state it is left in. However, Mario has to take care that no neighboring turtles are left in the same state, or otherwise they all will reunite and cause a fatal attack on Mario, as he is about to leave the alley.

The neighbors of turtle i are turtles i-1 and i+1. (Edited: If n >= 3,) The first and last turtles are not neighbors.

You need to find out the minimum amount of energy required to cross the alley.


first line contains no. of test cases T (T <= 5)
T input sets are given in the following manner:

  • the first line contains n, no. of turtles (n <= 20)
  • the next n lines have space separated 3 numbers (a1, a2, a3), the values of energy needed for ith turtle to change into states A D B (0 <= ai <= 1000)
  • similarly, the inputs are given for other cases


T lines, the minimal energy needed for each set of input


0 1 2
1 4 8
9 2 5
10 10 10
2 4 9
12 7 10
6 6 6


hide comments
dkkv0000: 2020-01-25 09:09:29

easy one

markomafko972: 2019-12-18 15:33:44

@fran_1024 like your dick

fran_1024: 2019-12-17 17:22:29

Why is n so small?

amulyagaur: 2017-12-12 05:10:46

Recursion : 0.04s
Recursion with memoization : 0.00s

rubenkresna22: 2017-09-24 05:38:09

ac in 1000000000000000 gos

nadstratosfer: 2017-09-12 04:37:58

6 years on and the input is still malformed. Lame.

surajmall: 2017-08-04 08:16:52

good dp probem for beginners :P

nikhil2504: 2017-07-26 19:20:14

Good for beginners like me.

NIKHIL KUMAR SINGH: 2017-01-08 17:13:34

So much of typing work.. Easy peasy.. AC in one go :)

Harshwardhan Bansal: 2016-10-01 13:04:51

New to DP...A very good problem to start... :)

Added by:Walrus
Time limit:0.100s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64
Resource:Local Contest: WPC 4