P23539 [AtCoder] Paired Wizards
NOI
题目描述

Problem Statement

Two wizards, X and Y, are fighting with a monster.
Initially, each of the wizards has a magic power of 0. They know the following two spells.

  • Spell 1: Increases the caster's magic power by 1.
  • Spell 2: Deals damage equal to the caster's magic power to the monster.

After each wizard uses a spell N times, they will withdraw from the battle.
For each $i=1, \ldots, N,$ they must use one of the following combinations of spells for their i-th spells.

  • X casts Spell a_i, and Y casts Spell b_i.
  • X casts Spell c_i, and Y casts Spell d_i.

Find the maximum total damage that can be dealt to the monster before the withdrawal.

Input

Input is given from Standard Input in the following format:
N
a_1 b_1 c_1 d_1
$\vdots$
a_N b_N c_N d_N

Output

Print the answer.

Constraints

  • $1 \leq N \leq 8000$
  • $a_i,b_i,c_i,d_i \in$ {1,2}
  • All values in input are integers.

Sample Input 1

3
1 1 2 2
2 1 2 2
2 1 1 1

Sample Output 1

3

The maximum total damage can be achieved as follows.

  • As the 1-st spells, use a_1=1,\, b_1=1, increasing both X's and Y's magic powers to 1.
  • As the 2-nd spells, use c_2=2,\, d_2=2, dealing 2 points of damage in total.
  • As the 3-rd spells, use a_3=2,\, b_3=1, dealing 1 point of damage by X's spell and increasing Y's magic power to 2.

Sample Input 2

5
2 2 2 2
2 2 2 2
2 2 2 2
2 2 2 2
2 2 2 2

Sample Output 2

0

Casting Spell 2 with a magic power of 0 deals no damage.

Sample Input 3

8
1 1 2 2
2 2 2 1
1 1 2 1
1 1 2 2
2 1 1 1
1 2 1 2
2 1 1 2
2 1 2 1

Sample Output 3

20

Sample Input 4

20
2 1 2 1
2 1 1 1
1 2 1 1
2 2 1 2
2 2 2 1
1 1 2 1
1 2 2 2
2 2 2 1
1 1 1 2
1 2 1 2
1 2 2 2
2 1 1 2
2 1 1 1
1 2 1 2
1 2 1 2
1 1 1 2
1 1 2 1
2 2 1 1
1 2 2 2
2 1 1 2

Sample Output 4

138

输入格式

见题面 Input 部分

输出格式

见题面 Output 部分

样例输入
3 1 1 2 2 2 1 2 2 2 1 1 1
样例输出
3