贪心/POJ 3069 Saruman's Army

 1 #include<cstdio>
 2 #include<cstring>
 3 #include<algorithm>
 4 using namespace std;
 5 int n,r,ans;
 6 int a[1010];
 7 int cmax(int x,int y){return x>y?x:y;}
 8 int main()
 9 {
10     scanf("%d%d",&r,&n);
11     while (n!=-1 && r!=-1)
12     {
13         memset(a,0,sizeof(a));
14         for (int i=1;i<=n;i++) scanf("%d",&a[i]);
15         sort(a+1,a+n+1);
16         int i=1;ans=0;
17         while (i<=n)
18         {
19             int s=a[i++];
20             while (i<=n && a[i]<=s+r) i++;
21             int p=a[i-1];
22             while (i<=n && a[i]<=p+r) i++;
23             ans++;
24         }
25         printf("%d\n",ans);
26         scanf("%d%d",&r,&n);
27     }
28     return 0;
29 }