http://www.1point3acres.com/bbs/thread-176388-1-1.html
you have 1 meter walkroad, and randomly generate rain, the rain is 1 cm. simulate how many rain drops to cover all the 1 meter [-0.01~1].
用merge intervals
https://moonstonelin.wordpress.com/2016/05/26/simulate-rain-in-1-meter-side-walk/
you have 1 meter walkroad, and randomly generate rain, the rain is 1 cm. simulate how many rain drops to cover all the 1 meter [-0.01~1].
用merge intervals
- static class Interval {
- double left = 0, right = 0.01;
- boolean isWet() {
- return left >= right;
- }. 1point 3acres 璁哄潧
- }
- public static void main(String[] args) {
- simulateRainDrop();
- }
- public static void simulateRainDrop() {
- . visit 1point3acres.com for more.
- Interval[] sidewalk = new Interval[100];
- for (int i = 0; i < 100; i++) {. 1point 3acres 璁哄潧
- sidewalk[i] = new Interval();
- }
- int cnt = 0, wetCnt = 0;
- while (wetCnt < 100) {. 鍥磋鎴戜滑@1point 3 acres
- ++cnt;
- double p = Math.random();
- double left = p - 0.005;
- double right = p + 0.005;
- if (left >= 0) {
- int idx = (int) (left / 0.01);
- if (!sidewalk[idx].isWet()) {
- double iright = left - idx * 0.01;
- if (iright < sidewalk[idx].right) {. 1point 3acres 璁哄潧
- sidewalk[idx].right = iright;
- if (sidewalk[idx].isWet())
- ++wetCnt;
- }. 涓€浜�-涓夊垎-鍦帮紝鐙鍙戝竷
- }. from: 1point3acres.com/bbs
- }
- if (right <= 1) {
- int idx = (int) (right / 0.01);
- if (!sidewalk[idx].isWet()) {
- double ileft = right - idx * 0.01;
- if (ileft > sidewalk[idx].left) {
- sidewalk[idx].left = ileft;
- if (sidewalk[idx].isWet())
- ++wetCnt;
- }.鏈枃鍘熷垱鑷�1point3acres璁哄潧
- }
- }
- }
- System.out.println(cnt);. more info on 1point3acres.com
- }
- }
| 定义一个 struct interv { double left=0, right=0.01; bool isWet() { return left>=right; } }; 就好了，然后生成0,1之间的一个均匀分布，模拟每个雨滴看落到哪个interval里，直. Waral 鍗氬鏈夋洿澶氭枃绔�, 到100个都打湿。 vector<interv> sidewalk(100,interv()); int cnt=0, wetCnt=0, idx; while(wetCnt<100) { ++cnt; double p= (double)(rand())/RAND_MAX; double left=p-0.005; double right=p+0.005; if(left>=0) {. 1point3acres.com/bbs idx=left/0.01; if(!sidewalk[idx].isWet()) { iright=left-idx*0.01; if (iright<sidewalk[idx].right) { sidewalk[idx].right=iright; if(sidewalk[idx].wet()) ++wetCnt; } } } if(right<=1) {. 鍥磋鎴戜滑@1point 3 acres idx=right/0.01; if(!sidewalk[idx].wet()) { ileft=right-idx*0.01;. From 1point 3acres bbs if (ileft>sidewalk[idx].left) { sidewalk[idx].left=ileft; if(sidewalk[idx].isWet()) ++wetCnt; } } } } |
https://moonstonelin.wordpress.com/2016/05/26/simulate-rain-in-1-meter-side-walk/
public void SimulateRainDrop() { SideWalk sideWalk = new SideWalk(100); while (!sideWalk.HasOccupied()) { Random random = new Random(); double start = random.Next(101) - 1 + random.NextDouble(); double end = start + 1; sideWalk.DropRain(start, end); Console.Write(start); Console.Write(" , "); Console.Write(end); Console.Write("\n"); } Console.WriteLine("occupied!"); }//start is the distance to 0, end is the distance to 1//both start and end fall into [0, 1]public class Interval{ public double Start { get; set; } public double End { get; set; } public bool IsCovered { get; set; } public Interval() { this.Start = 0; this.End = 0; this.IsCovered = false; }}public class SideWalk{ private int curOccupiedCount; public int Count; public Interval[] Intervals; public SideWalk(int count) { this.curOccupiedCount = 0; this.Count = count; this.Intervals = new Interval[count]; for (int i = 0; i < this.Count; i++) { this.Intervals[i] = new Interval(); } } // 1.68..2.68 public void DropRain(double start, double end) { int index = (int)Math.Floor(start); if (index >= 0) { if (Math.Abs(start - index) < 0.00001) { if (!this.Intervals[index].IsCovered) { this.curOccupiedCount++; this.Intervals[index].IsCovered = true; } return; } if (!this.Intervals[index].IsCovered) { this.Intervals[index].End = Math.Max(this.Intervals[index].End, index + 1 - start); if (this.Intervals[index].Start + this.Intervals[index].End >= 1) { this.Intervals[index].IsCovered = true; this.curOccupiedCount++; } } } if (index + 1 < this.Count) { if (!this.Intervals[index + 1].IsCovered) { this.Intervals[index + 1].Start = Math.Max(this.Intervals[index + 1].Start, end - index - 1); if (this.Intervals[index + 1].Start + this.Intervals[index + 1].End >= 1) { this.Intervals[index + 1].IsCovered = true; this.curOccupiedCount++; } } } } public bool HasOccupied() { return this.curOccupiedCount == this.Count; } }