poj 1036 Gangsters 简单dp

//poj 1036
//sep9
//这种dp效率低 会爆内存
#include <iostream>
using namespace std;
const int MAXT=30012;
const int MAXS=112;
const int MAXN=112;
int n,k,t;
int a[MAXT][MAXS];
int dp[MAXT][MAXS];
int x[MAXN],y[MAXN],z[MAXN];
int main()
{
scanf("%d%d%d",&n,&k,&t);
int maxT=0,maxS=0;
for(int i=0;i<n;++i){
scanf("%d",&x[i]);
maxT=max(maxT,x[i]);
}
for(int i=0;i<n;++i)
scanf("%d",&y[i]);
for(int i=0;i<n;++i){
scanf("%d",&z[i]);
maxS=max(maxS,z[i]);
}
memset(a,0,sizeof(a));
memset(dp,-1,sizeof(dp));
for(int i=0;i<n;++i)
a[x[i]][z[i]]+=y[i];
dp[0][0]=a[0][0];
for(int time=1;time<=maxT;++time)
for(int sta=0;sta<=MAXS;++sta){
if(sta-1>=0&&dp[time-1][sta-1]!=-1)
dp[time][sta]=max(dp[time][sta],dp[time-1][sta-1]+a[time][sta]);
if(dp[time-1][sta]!=-1)
dp[time][sta]=max(dp[time][sta],dp[time-1][sta]+a[time][sta]);
if(dp[time-1][sta+1]!=-1)
dp[time][sta]=max(dp[time][sta],dp[time-1][sta]+a[time][sta]);
}
int ans=-1;
for(int i=0;i<=MAXS;++i)
ans=max(ans,dp[maxT][i]);
if(ans==-1)
printf("0");
else
printf("%d",ans);
return 0;
}

//改变思考问题角度后的新dp AC
#include <iostream>
#include <algorithm>
using namespace std;

struct Node
{
int t,s,v;
}g[128];

int n,k,t;
int dp[128];

int cmp(Node x,Node y)
{
return x.t<y.t;
}

int main()
{
scanf("%d%d%d",&n,&k,&t);
for(int i=1;i<=n;++i)
scanf("%d",&g[i].t);
for(int i=1;i<=n;++i)
scanf("%d",&g[i].v);
for(int i=1;i<=n;++i)
scanf("%d",&g[i].s);
int ans=-1;
memset(dp,-1,sizeof(dp));
dp[0]=0;
g[0].t=0,g[0].s=0,g[0].v=0;
sort(g+1,g+1+n,cmp);
for(int i=1;i<=n;++i){
for(int j=0;j<i;++j){
if(dp[j]!=-1&&abs(g[i].s-g[j].s)<=g[i].t-g[j].t)
dp[i]=max(dp[i],dp[j]+g[i].v);
}
ans=max(ans,dp[i]);
}
printf("%d",ans==-1?0:ans);
return 0;
}