TYVJ 1305 最大子序和

 1 #include<iostream>
 2 #include<cstdio>
 3 using namespace std;
 4 int n,m,f[300010],p[300010],sum=0,tail,head,x,ans=0;
 5 int main()
 6 {
 7     scanf("%d%d",&n,&m);
 8     head=1,tail=2;
 9     for(int i=1;i<=n;i++){
10         scanf("%d",&x);sum+=x;
11         while(f[tail-1]>=sum && tail>head) tail--;
12         f[tail]=sum;p[tail]=i;
13         tail++;
14         while(i-p[head]>m) head++;
15         if(sum-f[head]>ans) ans=sum-f[head];
16     }
17     printf("%d\n",ans);
18     return 0;
19 }

 1 #include<iostream>
 2 #include<cstdio>
 3 #define maxn 1000010
 4 using namespace std;
 5 int l=0,r=0,n,m,a[maxn],q[maxn*2],f[maxn];
 6 int main()
 7 {
 8     scanf("%d%d",&n,&m);
 9     for(int i=1;i<=n;i++) scanf("%d",&a[i]);
10     for(int i=1;i<=n;i++){
11         while(l<r&&i-q[l]>m) l++;
12         f[i]=f[q[l]]+a[i];
13         while(l<r&&f[q[r]]>f[i]) r--;
14         q[++r]=i;
15     }
16     int ans=0x7f;
17     for(int i=n-m+1;i<=n;i++) ans=min(ans,f[i]);
18     printf("%d\n",ans);
19     return 0;
20 }