CSES - Robot Path
  • Time limit: 1.00 s
  • Memory limit: 512 MB
You are given a description of a robot's path. The robot begins at point $(0,0)$ and performs $n$ commands. Each command moves the robot some distance up, down, left or right.

The robot will stop when it has performed all commands, or immediately when it returns to a point that it has already visited. Your task is to calculate the total distance the robot moves.

Input

The first input line has an integer $n$: the number of commands.

After that, there are $n$ lines describing the commands. Each line has a character $d$ and an integer $x$: the robot moves the distance $x$ to the direction $d$. Each direction is U (up), D (down), L (left), or R (right).

Output

Print the total distance the robot moves.

Constraints
  • $1 \le n \le 10^5$
  • $1 \le x \le 10^6$
Example

Input:
5
U 2
R 3
D 1
L 5
U 2


Output:
9