首页 > 代码库 > HDU 1081 最大子矩阵和

HDU 1081 最大子矩阵和

2024-08-14 03:32:56   219人阅读

To The Max

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 11715    Accepted Submission(s): 5661


Problem Description
Given a two-dimensional array of positive and negative integers, a sub-rectangle is any contiguous sub-array of size 1 x 1 or greater located within the whole array. The sum of a rectangle is the sum of all the elements in that rectangle. In this problem the sub-rectangle with the largest sum is referred to as the maximal sub-rectangle.

As an example, the maximal sub-rectangle of the array:

0 -2 -7 0
9 2 -6 2
-4 1 -4 1
-1 8 0 -2

is in the lower left corner:

9 2
-4 1
-1 8

and has a sum of 15.
 

 

Input
The input consists of an N x N array of integers. The input begins with a single positive integer N on a line by itself, indicating the size of the square two-dimensional array. This is followed by N 2 integers separated by whitespace (spaces and newlines). These are the N 2 integers of the array, presented in row-major order. That is, all numbers in the first row, left to right, then all numbers in the second row, left to right, etc. N may be as large as 100. The numbers in the array will be in the range [-127,127].
 

 

Output
Output the sum of the maximal sub-rectangle.
 

 

Sample Input
4
0 -2 -7 0 9 2 -6 2-4 1 -4 1 -18 0 -2
 

 

Sample Output
15
 

 

Source
Greater New York 2001
 
题意：
题解：
 1 /****************************** 2 code by drizzle 3 blog: www.cnblogs.com/hsd-/ 4 ^ ^    ^ ^ 5  O      O 6 ******************************/ 7 //#include<bits/stdc++.h> 8 #include<iostream> 9 #include<cstring>10 #include<cmath>11 #include<cstdio>12 #define ll long long13 #define mod 100000000714 #define PI acos(-1.0)15 using namespace std;16 int main()17 {18     int a[105][105];19     int b[105];20     int n;21     while(scanf("%d",&n)!=EOF)22     {23         for(int i=1;i<=n;i++)24         {25             for(int j=1;j<=n;j++)26                 scanf("%d",&a[i][j]);27         }28         int maxn=-100000;29         for(int i=1;i<=n;i++)30         {31             memset(b,0,sizeof(b));32             for(int j=i;j<=n;j++)33             {34                 int sum=0;35                 for(int k=1;k<=n;k++)36                 {37                     b[k]+=a[j][k];38                     sum+=b[k];39                     if(sum<0) sum=b[k];40                     if(sum>maxn) maxn=sum;41                 }42             }43         }44         printf("%d\n",maxn);45     }46     return 0;47 }

 

 

HDU 1081 最大子矩阵和


联系
我们