hdu1712 分组背包 ACboy needs your help

ACboy needs your help

Time Limit: 1000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 5022 Accepted Submission(s): 2714


[align=left]Problem Description[/align]
ACboy
has N courses this term, and he plans to spend at most M days on
study.Of course,the profit he will gain from different course depending
on the days he spend on it.How to arrange the M days for the N courses
to maximize the profit?

[align=left]Input[/align]
The
input consists of multiple data sets. A data set starts with a line
containing two positive integers N and M, N is the number of courses, M
is the days ACboy has.
Next follow a matrix A[i][j],
(1<=i<=N<=100,1<=j<=M<=100).A[i][j] indicates if ACboy
spend j days on ith course he will get profit of value A[i][j].
N = 0 and M = 0 ends the input.

[align=left]Output[/align]
For each data set, your program should output a line which contains the number of the max profit ACboy will gain.

[align=left]Sample Input[/align]

2 2
1 2
1 3
2 2
2 1
2 1
2 3
3 2 1
3 2 1
0 0

[align=left]Sample Output[/align]

3
4
6

[align=left]Source[/align]
HDU 2007-Spring Programming Contest

#include<stdio.h>
#include<string.h>
#include<iostream>
#include<algorithm>
using namespace std;
int a[200][200];
int f[1000];
int main(){
int n,m;
while(scanf("%d%d",&n,&m)!=EOF){
if(n==0&&m==0)
break;
memset(f,0,sizeof(f));
memset(a,0,sizeof(a));
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++)
scanf("%d",&a[i][j]);
}

for(int i=1;i<=n;i++){
for(int j=m;j>=0;j--){
for(int k=1;k<=j;k++)
f[j]=max(f[j],f[j-k]+a[i][k]);
}
}
printf("%d\n",f[m]);
}
return 0;
}