返回一个二维整数数组中最大子数组的和

 1 //XiaoSong Du 2015/4/8
 2 #include <iostream>
 3 #include <time.h>
 4 using namespace std;
 5 #define M 3
 6 #define N 6
 7 
 8 void main()
 9 {
10     int a[M][N],b[N],d = 0,d1 = 0;
11     int maxd ,maxd1,end1[M][N] = {0},end2[M][N] = {0};
12     int i_max = 0,j_max = 0;
13 
14     srand((unsigned int)time(0));    
15 
16     for (int j = 0;j < M;j++)
17     {
18         for (int k = 0;k < N;k++)
19         {
20             a[j][k] = rand()%50 - 25;
21             cout << a[j][k] << " ";
22         }    
23         cout << endl;
24     }
25     cout << endl;    
26 
27     maxd = a[0][0];
28     maxd1 = a[0][0];
29     for (int i = 0;i < M;i++)//i为0，表示1行，i为1表示两行数···
30     {
31         for (int i_hang = 0;i_hang < M-i;i_hang++)//当1行是循环3次
32         {
33             for (int j = 0;j < N;j++)//赋初值
34             {
35                 b[j] = 0;
36             }
37             for (int i_hang1 = i_hang;i_hang1 <= i_hang+i;i_hang1++)//每次循环i次赋值
38             {
39                 for (int j = 0;j < N;j++)
40                 {
41                     b[j] += a[i_hang1][j];
42                 }
43             }
44             d = 0;
45             for (int k = 0;k < N;k++)
46             {
47                 d += b[k]; 
48                 if (d > maxd)
49                 {
50                     maxd = d;
51                     end1[i][i_hang] = k;
52                     i_max = i;       //最大的时候是i行；
53                     j_max = i_hang;   //
54                 }
55                 if(d < 0)
56                 {
57                     d = 0;
58                 }        
59             }        
60         
61             for (int k = N-1;k >= 0;k--)
62             {
63                 d1 += b[k];
64                 if (d1 > maxd1) 
65                 {
66                     maxd1 = d1;
67                     end2[i][i_hang] = k;
68                 }
69                 if(d1 < 0)
70                 {
71                     d1 = 0;
72                 }
73             }
74         
75         }
76     }
77     cout << "子数组为：" << endl;
78     for (int k = 0;k <= i_max;k++)
79     {
80         for (int k1 = end2[i_max][j_max];k1 <= end1[i_max][j_max];k1++)
81         {
82                 cout << a[j_max+k][k1] << " ";
83         }
84         cout << endl;
85     }
86     
87     cout << endl;
88     cout << "和为： " << maxd << endl;    
89 }