贪心/poj 1456 Supermarket

 1 #include<cstdio>
 2 #include<cstring>
 3 #include<algorithm>
 4 using namespace std;
 5 struct node
 6 {
 7     int value;
 8     int ddl;
 9 };
10 node a[10010];
11 bool day[10010];
12 int n,ans;
13 bool cmp(node x,node y)
14 {
15     return x.value>y.value;
16 }
17 int main()
18 {
19     while (scanf("%d",&n)!=EOF)
20     {
21         memset(a,0,sizeof(a));
22         memset(day,0,sizeof(day));
23         for (int i=1;i<=n;i++) scanf("%d%d",&a[i].value,&a[i].ddl);
24         sort(a+1,a+n+1,cmp);
25         ans=0;
26         for (int i=1;i<=n;i++)
27         {
28             int p=a[i].ddl;
29             while (p>0 && day[p]==1) p--;
30             if (p!=0)
31             {
32                 ans+=a[i].value;
33                 day[p]=1;
34             }
35         }
36         printf("%d\n",ans);
37     }
38     return 0;
39 }