Maximum Connectivity sub-array

Maximum Connectivity sub-array

After several iterations of the project to develop an array of items, the teacher then arranged the "Unicom array" task:

1. Title: Returns the number of the largest interconnected subarray in a two-dimensional integer group;

2, there are positive numbers in the array, there are negative numbers;

3, the maximum value of all sub-arrays, requiring a time complexity of O (n);

4, the program to use the array placed in the Input.txt file, the format of the file: the number of rows, the number of columns, each row of elements;

First, the experimental ideas

Second, the Experiment Code and implementation

The code is as follows:

1 //2016/4/1--Zhao Ziyin & Hole Aerospace2 3#include <iostream>4#include <fstream>5 using namespacestd;6 7 intMax (intNintArr[],int*start_mark,int*Final_mark)8 {9     intstep[ -] = {0};//Step Records Each step of the computed sub-array andTen     intI, sum =0, Max1 =0; One     /*Sum is a sub-array and A The MAX1 is the maximum and the sub-array -     */ -      for(i =0; i<n; i++) the     { -         if(sum<0) -sum =Arr[i]; -         Else +sum = sum +Arr[i]; -Step[i] =sum; +     } AMAX1 = step[0]; at      for(i =0; i<n; i++) -     { -         if(max1<Step[i]) -         { -Max1 =Step[i]; -*final_mark =i; in         } -     } to      for(i = *final_mark; I >=0; i--) +     { -         if(Step[i] = =Arr[i]) the         { **start_mark =i; $              Break;Panax Notoginseng         } -     } the     returnmax1; + } A  the voidMain () + { -     intm, N, I, J, Start_mark, Final_mark, big; $     intMax1; $     intread[10000];//read the character set of a file -     intup[ -], down[ -], h[ -]; -     intarr2[ -][ -], arr1[ -]; the     /*array of M row n columns - Start_mark indicates the starting coordinate of the largest subarrayWuyi Final_mark represents the terminating coordinate of the largest subarray the big represents the last output of the largest Unicom sub-array and - Max1 is the largest subarray of one-dimensional arrays returned by the function and Wu Up holds maximum sub-array start coordinates per line - Down holds maximum sub-array termination coordinates per line About h holds the maximum number of sub-arrays per row and $ ARR2 storing two-dimensional arrays - Arr1 A one-dimensional array of splits -     */ -  A     /*cout << "Please enter the number of rows and columns of the two-dimensional array:"; + cin >> m >> N; the cout << "Please enter this two-dimensional matrix:" << Endl; - For (i = 0; i<m; i++) $     { the For (j = 0; j<n; j + +) the         { the cin >> A[i][j]; the         } -     }*/ in  the     //file Input theIfstream infile ("Input.txt"Ios::inch); About     if(Infile.is_open () = =false) the     { theCerr <<"Open error!"<<Endl; theExit1); +     } -InFile >> read[0];//read number of rows M them = read[0];BayiInFile >> read[1];//read number of columns n then = read[1]; thecout <<"in the specified file"<< read[0] <<"Line"<< read[1] <<"the two-dimensional array of columns is as follows:"<<Endl; -      for(i =0; I < m; i++)//reading an array and outputting it in format -     { the          for(j =0; J < N; J + +) the         { theinfile >> Read[i +2]; theARR2[I][J] = read[i +2]; -cout << Arr2[i][j] <<" "; the             if(j% (N-1) ==0&& J! =0) the                 //if (j = = n-1) thecout <<Endl;94         } the     } the infile.close (); the 98     //decompose a two-dimensional array into several one-dimensional arrays by rows About      for(i =0; i<m; i++) -     {101          for(j =0; j<n; J + +)102         {103ARR1[J] =Arr2[i][j];104         } theMax1 = Max (n, Arr1, &start_mark, &Final_mark);106Up[i] =Start_mark;107Down[i] =Final_mark;108H[i] =Max1;109     } the 111Big = h[0]; the      for(i =0; i +1<m; i++)113     { the         if(Up[i] <= down[i +1] && Down[i] >= up[i +1])//Unicom, then add theBig + + H[i +1]; the          for(j = up[i]; J<up[i +1]; J + +)117         {118             if(Arr2[i +1][j]>0)//is independent positive, there is119Big + + Arr2[i +1][j];  -         }121     }122 123cout <<"The number of the largest interconnected sub-arrays of this two-dimensional array is:"<<Endl;124cout << Big <<Endl; the     126}

The results of the operation are as follows:

Third, the experience of experimental experiences

Maximum Connectivity sub-array