1 package test2;
  2 import java.io.BufferedReader;
  3 import java.io.File;
  4 import java.io.FileReader;
  5 import java.io.IOException;
  6 import java.util.ArrayList;
  7 import java.util.Scanner;
  8
  9 public class shuzu2 {
 10
 11     static Scanner cin = new Scanner(System.in);
 12
 13     public static void readFileByLines(String fileName) {
 14         File file = new File(fileName);
 15         BufferedReader reader = null;
 16         try {
 17             reader = new BufferedReader(new FileReader(file));
 18             String tempString = null;
 19
 20             while ((tempString = reader.readLine()) != null) {
 21
 22                 System.out.println(tempString);
 23
 24             }
 25             reader.close();
 26         } catch (IOException e) {
 27             e.printStackTrace();
 28         } finally {
 29             if (reader != null) {
 30                 try {
 31                     reader.close();
 32                 } catch (IOException e1) {
 33                 }
 34             }
 35         }
 36     }
 37
 38     public static long[] toArrayByFileReader1(String name) {
 39         // 使用ArrayList来存储每行读取到的字符串
 40         ArrayList<String> arrayList = new ArrayList<>();
 41         try {
 42             FileReader fr = new FileReader(name);
 43             BufferedReader bf = new BufferedReader(fr);
 44             String str;
 45             // 按行读取字符串
 46             while ((str = bf.readLine()) != null) {
 47                 arrayList.add(str);
 48             }
 49             bf.close();
 50             fr.close();
 51         } catch (IOException e) {
 52             e.printStackTrace();
 53         }
 54         // 对ArrayList中存储的字符串进行处理
 55         int length = arrayList.size();
 56         long[] array = new long[length];
 57         for (int i = 0; i < length; i++) {
 58             String s = arrayList.get(i);
 59             array[i] = Long.parseLong(s);
 60         }
 61         long[] newarray = new long[5*length];//剪开带子后新数组
 62         long[] result = new long[1000];//存放求和子数组
 63         int rs=0;//子数组计数器
 64         long f=0;//定义整形变量f，为子数组最大值
 65         long sum=0;//定义整形变量sum，为子数组求和
 66         System.out.println("输入遍历开始的位置：");
 67         int a = cin.nextInt();
 68         int sa = 0;//a用来存储剪开带子位置
 69         int k = 0 ;
 70         long []jieguo = new long[1000];
 71         for(int j = 0;j < array.length;j++)
 72         {
 73                 newarray[k++] = array[j];
 74                 newarray[j+array.length] = array[j];
 75                 //System.out.println("1   "+newarray[j]);
 76         }
 77         for(int i=0;i<2*array.length;i++)
 78         System.out.println("2    "+newarray[i]);
 79         int mlist,slist=0;
 80         long max;
 81         for(int i=0;i<length;i++)                        //O（n^2）求子数组之和
 82         {
 83             mlist = 0;
 84             for(int j=i;j<length+i;j++)
 85             {
 86                 mlist +=newarray[j];
 87                 result[rs++] = mlist;        //将子数组之和存在数组result[]内
 88                 System.out.println("第"+ (slist+1) +"个子数组的和为：" + mlist);
 89                 slist++;
 90             }
 91         }
 92         for(int i=0;i<rs;i++)
 93         {System.out.println("reslut"+i+"  "+result[i]);}
 94         max = result[0];                            //将子数组和数组第一个值给max，然后循环进行比较，求出最大值
 95         for(int i = 0;i<slist;i++)
 96         {
 97             if(max < result[i])
 98                 max = result[i];
 99         }
100         //将新数组存一下
101         System.out.println("该数组的子数组之和的最大值为："+max);
102         // 返回数组
103         return array;
104     }
105
106
107     public static void main(String[] args) throws IOException{
108
109         String name = new String("E:\\Program Files\\eclipse操作\\shuzu\\src\\test2\\input.txt");
110
111         readFileByLines(name);
112         toArrayByFileReader1(name);//文件路径
113
114     }
115 }