【POJ】2082 Terrible Sets

#include<cstdio>
#include<algorithm>
#define MAXN 50010
using namespace std;
struct node
{
    int w,h;
}st[MAXN];
int main()
{
    node temp;
    int i,j,n,ans,top,wide;
    while(scanf("%d",&n),n!=-1)
    {
        top=-1;
        for(ans=i=0;i<n;i++)
        {
            scanf("%d%d",&temp.w,&temp.h);
            for(wide=0;top>-1&&st[top].h>=temp.h;top--)
            {
                wide+=st[top].w;
                ans=max(ans,st[top].h*wide);
            }
            temp.w+=wide;
            st[++top]=temp;
        }
        for(wide=0;top>-1;top--)
        {
            wide+=st[top].w;
            ans=max(ans,st[top].h*wide);
        }
        printf("%d\n",ans);
    }
    return 0;
}