#P7069. [NWRRC 2014] Joy of Flight

[NWRRC 2014] Joy of Flight

题目描述

Jacob likes to play with his radio-controlled aircraft. The weather today is pretty windy and Jacob has to plan flight carefully. He has a weather forecast — the speed and direction of the wind for every second of the planned flight.

The plane may have airspeed up to vmaxv_{\max} units per second in any direction. The wind blows away plane in the following way: if airspeed speed of the plane is (vx,vy)(v_x, v_y) and the wind speed is (wx,wy)(w_x, w_y), the plane moves by (vx+wx,vy+wy)(v_x+w_x, v_y+w_y) each second.

Jacob has a fuel for exactly kk seconds, and he wants to learn, whether the plane is able to fly from start to finish in this time. If it is possible he needs to know the flight plan: the position of the plane after every second of flight.

输入格式

The first line of the input file contains four integers Sx,Sy,Fx,FyS_x, S_y, F_x, F_y — coordinates of start and finish (10000Sx,Sy,Fx,Fy10000−10 000 ≤ S_x, S_y, F_x, F_y ≤ 10 000).

The second line contains three integers n,kn, k and vmaxv_{\max} — the number of wind condition changes, duration of Jacob’s flight in seconds and maximum aircraft speed (1n,k,vmax100001 ≤ n, k, v_{\max} ≤ 10 000).

The following nn lines contain the wind conditions description. The ii-th of these lines contains integers ti,wxit_i, w_{x_i} and wyiw_{y_i} — starting at time tit_i the wind will blow by vector (wxi,wyi)(w_{x_i}, w_{y_i}) each second ($0 = t_1 < ··· < t_i < t_{i+1} < ··· < k; \sqrt{w_{x_i}^2 + w_{y_i}^2} ≤ v_{\max}$).

输出格式

The first line must contain Yes if Jacob’s plane is able to fly from start to finish in k seconds, and No otherwise.

If it can to do that, the following kk lines must contain the flight plan. The ii-th of these lines must contain two floating point numbers xx and yy — the coordinates of the position (PiP_i) of the plane after ii-th second of the flight.

The plan is correct if for every 1ik1 ≤ i ≤ k it is possible to fly in one second from Pi1P_{i−1} to some point QiQ_i, such that distance between QiQ_i and PiP_i doesn’t exceed 10510^{−5}, where P0=SP_0 = S. Moreover the distance between PkP_k and FF should not exceed 10510^{-5} as well.

1 1 7 4
2 3 10
0 1 2
2 2 0
Yes
3 2.5
5 2.5
7 4

提示

Time limit: 2 s, Memory limit: 256 MB.