POJ.3684 Physics Experiment

1.Problem
http://poj.org/problem?id=3684

2.Idea
Assume each of ball is transparent and could pass by one another when collide.

3.Source

 #define MAX_N 111  
 const double g = 10.0;  
 int N, H, R, T;  
 double y[MAX_N];  
 double calc(int T)  
 {  
      if (T < 0) return H;  
      double t = sqrt(2 * H / g);  
      int k = int(T / t);  
      if (k % 2 == 0) {  
           double d = T - k*d;  
           return H - g * d *d / 2;  
      }  
      else {  
           double d = k * t + t - T;  
           return H - g * d *d / 2;  
      }  
 }  
 void solve()  
 {  
      for (int i = 0; i < N; i++) y[i] = calc(T - i);  
      sort(y, y + N);  
      for (int i = 0; i < N; i++) {  
           printf("%.2f%c", y[i] + 2 * R * i / 100.0, i + 1 == N ? '\n' : ' ');  
      }  
 }  
 int main()  
 {  
      int c;  
      cin >> c;  
      while (c--) {  
           cin >> N >> H >> R >> T;  
           solve();  
      }  
      return 0;  
 }