FatMouse's Speed--hdu1160(dp+输出路径)

#include<stdio.h>
#include<string.h>
#include<math.h>
#include<algorithm>
#include<iostream>
#include<math.h>
#include<stdlib.h>

using namespace std;

#define INF 0xfffffff
#define N 5000

struct node
{
    int num,w,s;
}a[N];

int cmp(const void *x,const void *y)
{
    struct node *c,*d;
    c=(struct node *)x;
    d=(struct node *)y;
    if(c->w!=d->w)
    return c->w-d->w;
    else
        return d->s-c->s;
}
int main()
{
    int i=0,pre[N],dp[N];
    while(scanf("%d %d",&a[i].w,&a[i].s)!=EOF)
    {
        dp[i]=1;
        pre[i]=0;
        a[i].num=i+1;
        i++;
    }
    int n=i,b,Max=0;
    qsort(a,n,sizeof(a[0]),cmp);
    for(i=0;i<n;i++)
    {
        for(int j=0;j<i;j++)
        {
            if(a[j].w<a[i].w&&a[j].s>a[i].s&&dp[j]+1>dp[i])
            {
                dp[i]=dp[j]+1;
                pre[i]=j;
                if(Max<dp[i])
                {
                    b=i;
                    Max=dp[i];
                }
            }
        }
    }
    int aa[N];
    printf("%d\n",Max);
    aa[0]=a[b].num;
    i=1;
    while(1)
    {
        int j=pre[b];
        if(j==0)
            break;
        aa[i++]=a[j].num;
        b=j;
    }
    for(int j=i-1;j>=0;j--)
        printf("%d\n",aa[j]);
    return 0;
}