poj 1276 dp多重背包

2015/2/12

简单的多重背包

只不过数据不太水，不能用10背包来水过

我用的是拆包。。

就这样。。

#include<map>
#include<queue>
#include<stack>
#include<cmath>
#include<vector>
#include<climits>
#include<stdio.h>
#include<string.h>
#include<iostream>
#include<algorithm>

using namespace std;
typedef long long ll;  

#define mod 10007
#define lson pos<<1,l,mid
#define sc(n) scanf("%d",&n)
#define rson pos<<1|1,mid+1,r
#define pr(n) printf("%d\n",n)
#define met(n,m) memset(n, m, sizeof(n))
#define F(x,y,i) for(int i = x;i > y; i--)
#define f(x,y,i) for(int i = x;i < y; i++)
#define ff(x,y,i) for(int i = x;i <= y; i++)
#define FF(x,y,i) for(int i = x;i >= y; i--) 

const int N=100500;
const int inf = INT_MAX;

int Max(int a,int b)
{
	return a>b?a:b;
}

int Min(int a,int b)
{
	return  a<b?a:b;
}

int v[15];
int c[15];

int dp[100005];

int main()  
{  
    int n, m, sum, tot, x;
    while(~scanf("%d%d",&sum,&n))
    {
		f(0,n,i)
		scanf("%d%d",&c[i],&v[i]);
		
		met(dp,0);
		
		f(0,n,i)
		{
			if(c[i]*v[i] >= sum)
			{
				f(v[i],sum+1,j)
				{
					dp[j] = Max(dp[j],dp[j - v[i]] + v[i]);
				}
			}
			
			else
			{
				int k ,num;
				 num = c[i];
				 k = 1;
				while(k <= num)
				{
					for(int j = sum;j >= k*v[i]; j--)
					{
						dp[j]=Max(dp[j],dp[j-k*v[i]]+k*v[i]);
					}
					num-=k;
					k<<=1;
					
				}
				
				for(int j = sum;j >= num*v[i]; j--)  
                {  
                	dp[j]=Max(dp[j],dp[j-num*v[i]] +num*v[i]);  
                }  
				
			}
			
			
		}  
		    	
		    	pr(dp[sum]);
    }
    return 0;  
}