HDU 1085 Holding BinLaden Captive! (母函数 | 多重背包)

Holding Bin-Laden Captive!

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 11029    Accepted Submission(s): 4943

Problem Description

We all know that Bin-Laden is a notorious terrorist, and he has disappeared for a long time. But recently, it is reported that he hides in Hang Zhou of China!  “Oh, God! How terrible! ”Don’t be so afraid, guys. Although he hides in a cave of Hang Zhou, he dares not to go out. Laden is so bored recent years that he fling himself into some math problems, and he said that if anyone can solve his problem, he will give himself up!  Ha-ha! Obviously, Laden is too proud of his intelligence! But, what is his problem? “Given some Chinese Coins (硬币) (three kinds-- 1, 2, 5), and their number is num_1, num_2 and num_5 respectively, please output the minimum value that you cannot pay with given coins.” You, super ACMer, should solve the problem easily, and don’t forget to take $25000000 from Bush!

 

Input

Input contains multiple test cases. Each test case contains 3 positive integers num_1, num_2 and num_5 (0<=num_i<=1000). A test case containing 0 0 0 terminates the input and this test case is not to be processed.

 

Output

Output the minimum positive value that one cannot pay with given coins, one line for one case.

 

Sample Input

1 1 3

0 0 0

 

Sample Output

4

 

Author

lcy

 

 

 1,母函数：

#include<iostream>
#include<cstdio>
#include<cstring>

using namespace std;

const int N=8010;

int num[4],money[4]={0,1,2,5};
int c1[N],c2[N];

int main(){

    //freopen("input.txt","r",stdin);

    while(~scanf("%d%d%d",&num[1],&num[2],&num[3])){
        if(num[1]==0 && num[2]==0 && num[3]==0)
            break;
        for(int i=0;i<N;i++){
            c1[i]=0;
            c2[i]=0;
        }
        c1[0]=1;
        int maxx=0;
        for(int i=1;i<=3;i++){
            maxx+=num[i]*money[i];
            for(int j=0;j<=maxx;j++)
                for(int k=0;k<=num[i] && j+k*money[i]<=maxx;k++)
                    c2[j+k*money[i]]+=c1[j];
            for(int j=0;j<=maxx;j++){
                c1[j]=c2[j];
                c2[j]=0;
            }
        }
        for(int i=1;;i++)
            if(c1[i]==0){
                printf("%d\n",i);
                break;
            }
    }
    return 0;
}

2,多重背包：

#include<iostream>
#include<cstdio>
#include<cstring>

using namespace std;

int num[3],money[3]={1,2,5};
int dp[8010];

int main(){

    //freopen("input.txt","r",stdin);

    while(~scanf("%d%d%d",&num[0],&num[1],&num[2])){
        if(num[0]==0 && num[1]==0 && num[2]==0)
            break;
        memset(dp,0,sizeof(dp));
        int tot=num[0]*1+num[1]*2+num[2]*5;
        dp[0]=1;
        for(int i=0;i<3;i++)    //简单的多重背包
            for(int j=0;j<num[i];j++)
                for(int k=tot;k>=money[i];k--)
                    dp[k]+=dp[k-money[i]];
        int ans=tot+1;
        for(int i=1;i<=tot;i++)
            if(dp[i]==0){
                ans=i;
                break;
            }
        printf("%d\n",ans);
    }
    return 0;
}