package Level4;import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;public class PE0102{public static void run(){int count = 0;ArrayList<int[]> list = readData();for(int i=0;i<list.size();i++){int arr[] = list.get(i);if(iscontainmentTriangle(arr)){count+=1;}if(i<10)System.out.println(iscontainmentTriangle(arr));}System.out.println(count);}// 判断原点是否在三角形内部public static boolean iscontainmentTriangle(int[] arr){int count =0;for(int i=0;i<arr.length-1;i+=2){int x1 = arr[i];int y1 = arr[i+1];for(int j=i+2;j<arr.length-1;j+=2){int x2 = arr[j];int y2 = arr[j+1];if(isObtuseAngle(x1,y1,x2,y2))count ++;if(count ==2)return true;}}return false;}// 是不是钝角public static boolean isObtuseAngle(int x1,int y1,int x2,int y2){long costheta = x1*y1 + x2*y2;if(costheta <0)return true;return false;}// 转换成整型数组public static int [] StringtoInt(String[] strArr){int[] IntArr = new int[strArr.length];for(int i=0;i<strArr.length;i++)IntArr[i] = Integer.parseInt(strArr[i]);return IntArr;}// 读取数据public static ArrayList<int[]> readData(){String filename= "src/Level4/p102_triangles.txt";ArrayList<int[]> list = new ArrayList<int[]>();try {BufferedReader bufferedReader = new BufferedReader(new FileReader(filename));String line = "";while((line=bufferedReader.readLine())!=null){String[] strArr = line.split(",");list.add(StringtoInt(strArr));}} catch (FileNotFoundException e) {// TODO Auto-generated catch block
            e.printStackTrace();} catch (IOException e) {// TODO Auto-generated catch block
            e.printStackTrace();}return list;}public static void main(String[] args){long t0 = System.currentTimeMillis();run();long t1 = System.currentTimeMillis();long t = t1 - t0;System.out.println("running time="+t/1000+"s"+t%1000+"ms");}
}

Java Code

package Level4;import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;public class PE0102{public static void run(){int count = 0;ArrayList<int[]> list = readData();for(int i=0;i<list.size();i++){int arr[] = list.get(i);if(iscontainmentTria(arr)){count+=1;}}System.out.println(count);
//        228
//        running time=0s16ms
    }// 判断原点是否在三角形内部public static boolean iscontainmentTria(int[] arr){int area = 0;int count =0;int X1 = arr[0] - arr[2];int Y1 = arr[1] - arr[3];int X2 = arr[4] - arr[2];int Y2 = arr[5] - arr[3];int area2 = area(X1,Y1,X2,Y2);for(int i=0;i<arr.length-1;i+=2){int x1 = arr[i];int y1 = arr[i+1];for(int j=i+2;j<arr.length-1;j+=2){int x2 = arr[j];int y2 = arr[j+1];area +=area(x1,y1,x2,y2);}}if(area == area2)return true;return false;}// 这里面积的二倍public static int area(int X1,int Y1,int X2,int Y2){int area = Math.abs(X1*Y2 - X2*Y1);return area;}// 转换成整型数组public static int [] StringtoInt(String[] strArr){int[] IntArr = new int[strArr.length];for(int i=0;i<strArr.length;i++)IntArr[i] = Integer.parseInt(strArr[i]);return IntArr;}// 读取数据public static ArrayList<int[]> readData(){String filename= "src/Level4/p102_triangles.txt";ArrayList<int[]> list = new ArrayList<int[]>();try {BufferedReader bufferedReader = new BufferedReader(new FileReader(filename));String line = "";while((line=bufferedReader.readLine())!=null){String[] strArr = line.split(",");list.add(StringtoInt(strArr));}} catch (FileNotFoundException e) {// TODO Auto-generated catch block
            e.printStackTrace();} catch (IOException e) {// TODO Auto-generated catch block
            e.printStackTrace();}return list;}public static void main(String[] args){long t0 = System.currentTimeMillis();run();long t1 = System.currentTimeMillis();long t = t1 - t0;System.out.println("running time="+t/1000+"s"+t%1000+"ms");}
}

# coding=gbkimport time as time
import re
import math
import numpy as np
def run():filename = 'E:/java/projecteuler/src/Level4/p102_triangles.txt'mat = readData(filename)mat = np.array(mat)count = 0for line in mat:if isContainmentTraingle(line):count+=1print count def isContainmentTraingle(triangle):X1 = triangle[0] - triangle[2]Y1 = triangle[1] - triangle[3]X2 = triangle[4] - triangle[2]Y2 = triangle[5] - triangle[3]S = area(X1,Y1,X2,Y2)for i in range(0,4,2):for j in range(i+2,5,2):S -= area(triangle[i],triangle[i+1],triangle[j],triangle[j+1])return S == 0def area(x1,y1,x2,y2):S = np.abs(x1*y2 - x2*y1)return Sdef readData(filename):mat = list()file = open(filename)for line in file:row = line.split(',')row = [int(x) for x in row]mat.append(row)return mat t0 = time.time()
run()
t1 = time.time()
print "running time=",(t1-t0),"s"