hdu1114 Piggy-Bank

我的代码没有通过，用了完全背包解法

#include "iostream"
#include "string.h"
#include "algorithm"
using namespace std;
struct {
  int p,w;
}num[1000];
int minb(int a,int b){return a>b?b:a;}

int main(){
  int Case,a,b,weight,n,i,s,m,top,min,j,k,visit[1100],f[1100],t;
  cin>>Case;
  while(Case--){
   cin>>a>>b;
   weight=b-a;
   cin>>n;
   for(i=1;i<=n;i++)cin>>num[i].p>>num[i].w;
   if(a<1||a>b){cout<<"This is impossible."<<endl;continue;}
   if(weight==0){cout<<"The minimum amount of money in the piggy-bank is 0."<<endl;continue;}
   top=n+1;
   for(i=1;i<=n;i++){
     if(num[i].w==1){
       s=1;m=weight-num[i].w;
       while(m>0){
         num[top].p=s*num[i].p;num[top].w=s*num[i].w;
         top++;
         s=2*s;
         m=m-s*num[i].w;
       }
       m=m+s*num[i].w;
       num[i].p=m/num[i].w*num[i].p;
       num[i].w=m;
     }
     else{
       s=2;m=weight-2*num[i].w;
       while(m>=0){
         num[top].p=s*num[i].p;num[top].w=s*num[i].w;
         top++;
         s=2*s;
         m=m-s*num[i].w;
       }
       m=m+s*num[i].w;
       if(m>num[i].w){
       num[top].p=m/num[i].w*num[i].p;
       num[top].w=(m/num[i].w)*num[i].w;
       top++;
       }
     }

   }
   //for(i=1;i<top;i++)cout<<"i.p "<<num[i].p<<" i.w "<<num[i].w<<endl;
   for(i=1;i<=weight;i++)f[i]=99999999;
   memset(visit,0,sizeof(visit));
   //for(i=1;i<=weight;i++)cout<<visit[i]<<' ';cout<<endl;
   min=99999999;visit[0]=1;
   for(i=1;i<top;i++){
     for(j=weight;j>=num[i].w;j--){
       if(visit[j-num[i].w]){
         visit[j]=1;
         f[j]=minb(f[j],f[j-num[i].w]+num[i].p);
         //cout<<j<<' '<<f[j]<<"**"<<endl;system("pause");
       }
     }
     if(visit[weight]){min=minb(min,f[weight]);visit[weight]=0;f[weight]=99999999;}
     //cout<<i<<' ';for(j=1;j<=weight;j++)cout<<f[j]<<' ';cout<<endl;
   }

   if(min==99999999)cout<<"This is impossible."<<endl;
   else cout<<"The minimum amount of money in the piggy-bank is "<<min<<"."<<endl;
  }
}

人家通过的代码，思路一对，什么都简单了，它是用了我之前有考虑到，但是没有用好，所以重新写了，重新写后，错了，嘻嘻嘻

#include<cstdio>
#include<cstring>
#include<algorithm>
#define INF 1000000000
using namespace std;
int dp[20000],P[1000],W[1000],E,F,N,M;
int main(void)
{
    int T,i,j;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d%d",&E,&F);
        M=F-E;
        scanf("%d",&N);
        for(i=0;i<N;i++)
            scanf("%d%d",&P[i],&W[i]);
        dp[0]=0;
        for(i=1;i<=M;i++)
           dp[i]=INF;
        for(i=0;i<N;i++)
           for(j=W[i];j<=M;j++)
              dp[j]=min(dp[j-W[i]]+P[i],dp[j]);
        if(dp[M]<INF)
           printf("The minimum amount of money in the piggy-bank is %d.
",dp[M]);
        else
           printf("This is impossible.
");
    }
    return 0;
}