poj 1276 Cash Machine_多重背包

题意：略

多重背包

#include <iostream>
#include<cstring>
#include<cstdio>
using namespace std;
#define MAXV 15
#define MAXM 100050

int cash,n,value[MAXV],c[MAXV],f[MAXM],user[MAXM];

int main(){
	int i,j,max;
	while(~scanf("%d%d",&cash,&n)){
		for(i=1;i<=n;i++)
			scanf("%d%d",&c[i],&value[i]);

		memset(f,0,sizeof(f));
		f[0]=1;
		max=0;

		for(i=1;i<=n;i++){
			memset(user,0,sizeof(user));
			for(j=value[i];j<=cash;j++)
				if(!f[j] && f[j-value[i]] && user[j-value[i]]+1<=c[i]){
					user[j]=user[j-value[i]]+1;
					f[j]=1;		//j为1，即j是可取的，选出可取的最大的j就是答案
					if(j>max) max=j;
				}
		}
		printf("%d\n",max);

	}
	return 0;
}