[TyvjP1313] [NOIP2010初赛]烽火传递（单调队列 + DP）

 1 #include <cstdio>
 2 
 3 const int MAXN = 1000001;
 4 int n, m, h = 1, t = 1, ans = ~(1 << 31);
 5 int q[MAXN], a[MAXN], f[MAXN];
 6 
 7 inline int min(int x, int y)
 8 {
 9     return x < y ? x : y;
10 }
11 
12 int main()
13 {
14     int i;
15     scanf("%d %d", &n, &m);
16     for(i = 1; i <= n; i++) scanf("%d", &a[i]);
17     for(i = 1; i <= n; i++)
18     {
19         while(h <= t && q[h] < i - m) h++;
20         f[i] = f[q[h]] + a[i];
21         while(h <= t && f[q[t]] > f[i]) t--;
22         q[++t] = i;
23      }
24      for(i = n - m + 1; i <= n; i++) ans = min(ans, f[i]);
25      printf("%d\n", ans);
26      return 0;
27 }