hdu 1506 dp

#include<iostream>
#include<cstring>
#include<algorithm>
#include<cstdio>
#include<vector>
#include<sstream>
#include<string>
#include<climits>
#include<stack>
#include<set>
#include<bitset>
#include<cmath>
#include<deque>
#include<map>
#include<queue>
#define iinf 0x7f7f7f7f
#define linf 1000000000000000000LL
#define dinf 1e200
#define eps 1e-11
#define all(v) (v).begin(),(v).end()
#define sz(x)  x.size()
#define pb push_back
#define mp make_pair
#define lng long long
#define sqr(a) ((a)*(a))
#define pii pair<int,int>
#define pll pair<lng,lng>
#define pss pair<string,string>
#define pdd pair<double,double>
#define X first
#define Y second
#define pi 3.14159265359
#define ff(i,xi,n) for(int i=xi;i<=(int)(n);++i)
#define ffd(i,xi,n) for(int i=xi;i>=(int)(n);--i)
#define ffl(i,r) for(int i=head[r];i!=-1;i=edge[i].next)
#define ffe(i,r) for(_edge *i=head[r];i;i=i->next)
#define cc(i,j) memset(i,j,sizeof(i))
#define two(x)          ((lng)1<<(x))
#define lson l , mid , rt << 1
#define rson mid + 1 , r , rt << 1 | 1
#define mod  1073741824
#define pmod(x,y) (x%y+y)%y
using namespace std;
typedef vector<int>  vi;
typedef vector<string>  vs;
template<class T> inline void checkmax(T &x,T y)
{
    if(x<y) x=y;
}
template<class T> inline void checkmin(T &x,T y)
{
    if(x>y) x=y;
}
template<class T> inline T Min(T x,T y)
{
    return (x>y?y:x);
}
template<class T> inline T Max(T x,T y)
{
    return (x<y?y:x);
}
template<class T> T Abs(T a)
{
    return a>0?a:(-a);
}
template<class T> inline T lowbit(T n)
{
    return (n^(n-1))&n;
}
template<class T> inline int countbit(T n)
{
    return (n==0)?0:(1+countbit(n&(n-1)));
}
#define N 111111
lng n,l[N],r[N];
lng h[N];
lng ans,temp;
int main()
{
  while(scanf("%I64d",&n)==1&&n)
  {
      ff(i,1,n) scanf("%I64d",h+i);
      l[1]=1;
      ff(i,2,n)
      {
          l[i]=i;
          while(l[i]>=2&&h[l[i]-1]>=h[i])
          l[i]=l[l[i]-1];
      }
      r[n]=n;
      ffd(i,n-1,1)
      {
          r[i]=i;
          while(r[i]<=n-1&&h[r[i]+1]>=h[i])
          r[i]=r[r[i]+1];
      }
      ans=0;
      ff(i,1,n)
      checkmax(ans,h[i]*(r[i]-l[i]+1));
      printf("%I64d
",ans);
  }
    return 0;
}

다음은 단조로운 대기열 최적화 버전입니다.

#include<iostream>
#include<cstring>
#include<algorithm>
#include<cstdio>
#include<vector>
#include<sstream>
#include<string>
#include<climits>
#include<stack>
#include<set>
#include<bitset>
#include<cmath>
#include<deque>
#include<map>
#include<queue>
#define iinf 0x7f7f7f7f
#define linf 1000000000000000000LL
#define dinf 1e200
#define eps 1e-11
#define all(v) (v).begin(),(v).end()
#define sz(x)  x.size()
#define pb push_back
#define mp make_pair
#define lng long long
#define sqr(a) ((a)*(a))
#define pii pair<int,int>
#define pll pair<lng,lng>
#define pss pair<string,string>
#define pdd pair<double,double>
#define X first
#define Y second
#define pi 3.14159265359
#define ff(i,xi,n) for(int i=xi;i<=(int)(n);++i)
#define ffd(i,xi,n) for(int i=xi;i>=(int)(n);--i)
#define ffl(i,r) for(int i=head[r];i!=-1;i=edge[i].next)
#define ffe(i,r) for(_edge *i=head[r];i;i=i->next)
#define cc(i,j) memset(i,j,sizeof(i))
#define two(x)          ((lng)1<<(x))
#define lson l , mid , rt << 1
#define rson mid + 1 , r , rt << 1 | 1
#define mod  1073741824
#define pmod(x,y) (x%y+y)%y
using namespace std;
typedef vector<int>  vi;
typedef vector<string>  vs;
template<class T> inline void checkmax(T &x,T y)
{
    if(x<y) x=y;
}
template<class T> inline void checkmin(T &x,T y)
{
    if(x>y) x=y;
}
template<class T> inline T Min(T x,T y)
{
    return (x>y?y:x);
}
template<class T> inline T Max(T x,T y)
{
    return (x<y?y:x);
}
template<class T> T Abs(T a)
{
    return a>0?a:(-a);
}
template<class T> inline T lowbit(T n)
{
    return (n^(n-1))&n;
}
template<class T> inline int countbit(T n)
{
    return (n==0)?0:(1+countbit(n&(n-1)));
}
#define N 111111
lng l[N],re[N];
lng h[N];
lng ans;
int ncase;
int n;
int q[N],r,f;
int main()
{
    while(scanf("%d",&n)==1)
    {
        if(n==0) break;
        ff(i,1,n) scanf("%I64d",h+i);
        ff(i,1,n) re[i]=n,l[i]=1;
        r=0;f=1;
        ff(i,1,n)
        {
            while(r>=f&&h[q[r]]>h[i])
            re[q[r]]=i-1,--r;
            q[++r]=i;
        }
        r=0;f=1;
        ffd(i,n,1)
        {
              while(r>=f&&h[q[r]]>h[i])
            l[q[r]]=i+1,--r;
            q[++r]=i;
        }
        ans=0;
        ff(i,1,n)
        checkmax(ans,h[i]*(re[i]-l[i]+1));
        printf("%I64d
",ans);
    }
    return 0;
}