HDU2602-Bone Collector

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i- i-th former article, k- volume, a [i] - the volume of the i-th item, b [i] - i-th value of the goods

State transition equation: f [i] [k] = max (f [i-1] [k], f [i-1] [ka [i]] + b [i]);

#include<iostream>
using namespace std;
int f[1005][1005];
int main(){
    int i,k,m,n,v,a[1005],b[1005];
    cin>>m;
    while(m--){
    cin>>n>>v;
    for(i=1;i<=n;i++) cin>>b[i];//价值
    for(i=1;i<=n;i++) cin>>a[i];//体积
    for(i=1;i<=n;i++)
    for(k=0;k<=v;k++)
    f[i][k]=0;
    for(i=1;i<=n;i++)
    for(k=0;k<=v;k++){
    if(k-a[i]>=0&&f[i-1][k]<f[i-1][k-a[i]]+b[i])
    f[i][k]=f[i-1][k-a[i]]+b[i];
    else
    f[i][k]=f[i-1][k];
    }
    cout<<f[n][v]<<endl;
    }
return 0;
} 

　Scroll array optimization

#include<iostream>
using namespace std;
int f[105][2];
int main(){
    int i,k,m,n,v,a[1005],b[1005];
    cin>>m;
    while(m--){
    cin>>n>>v;
    for(i=1;i<=n;i++) cin>>b[i];
    for(i=1;i<=n;i++) cin>>a[i];
    for(i=1;i<=n;i++)
    for(k=0;k<=v;k++)
    {
    if(k-a[i]>=0&&f[k][(i-1)%2]<f[k-a[i]][(i-1)%2]+b[i])
    f[k][i%2]=f[k-a[i]][(i-1)%2]+b[i];
    else
    f[k][i%2]=f[k][(i-1)%2];
    }
    cout<<f[v][(i-1)%2]<<endl;
    }
return 0;
}

A decreasing volume of the transition state

#include<iostream>
using namespace std;
int f[1005];
int main(){
    int i,k,m,n,v,a[1005],b[1005];
    cin>>m;
    while(m--){
    cin>>n>>v;
    for(i=1;i<=n;i++) cin>>b[i];//价值
    for(i=1;i<=n;i++) cin>>a[i];//体积
    for(k=0;k<=v;k++)
    f[k]=0;
    for(i=1;i<=n;i++)
    for(k=v;k>=0;k--)
    if(k>=a[i])
    f[k]=max(f[k],f[k-a[i]]+b[i]);
    cout<<f[v]<<endl;
    }
return 0;
}