시간 제한메모리 제한제출정답맞힌 사람정답 비율
1 초 128 MB100252028.169%

문제

Farmer John has purchased the world's most loathesome hay baler. Instead of having a drive-roller that drives maybe an idler roller that drives the power take-off for the baler, it has N rollers (2 <= N <= 1050) which drive and are driven by various rollers.

FJ has meticulously cataloged data for each roller i: X_i,Y_i are the center of the roller (-5000 <= X_i <= 5000; -5000 <= Y_i <= 5000); R_i is the roller's radius (3 <= R_i <= 800). The drive-roller is located at 0,0; the baler power take-off is located at X_t,Y_t (numbers supplied in the input).

The drive-roller turns clockwise at 10,000 revolutions per hour. Your job is to determine the speeds of all the rollers that are in the power-train: from the drive-roller through the power take-off roller. Rollers that do not transfer power to the take-off roller are to be ignored. A roller of radius Rd that is turning at S rph and driving another roller of radius Rx will cause the second roller to turn at the speed -S*Rd/Rx (where the sign denotes whether the roller is turning clockwise or counterclockwise (anticlockwise for our British friends)).

Determine the power-train path and report the sum of the absolute values of all those rollers' speeds. All the rollers in the input set except the driver-roller are driven by some other roller; power is never transferred to a roller from more than one other roller.

Report your answer as an integer that is the truncated value after summing all the speeds.

입력

• Line 1: Three space-separated integers: N, X_t, and Y_t
• Lines 2..N+1: Line i+1 describes roller i's properties: X_i, Y_i, and R_i

출력

• Line 1: A single integer that is the truncated version of the sum of the absolute value of the speeds of the rollers in the power-train including the drive-roller, all the driven rollers, and the power take-off roller.

예제 입력 1

4 32 54
0 0 10
0 30 20
32 54 20
-40 30 20


예제 출력 1

20000


힌트

 Roller   Radius   Speed
1 (0,0)     10     10,000
2 (0,30)    20     -5,000
3 (32,54)   20      5,000
------
Sum of abs values: 20,000