好消息，坏消息
1 #include<iostream> 2 #include<cstdio> 3 using namespace std; 4 typedef long long ll; 5 const int maxn=2e6+7; 6 ll val[maxn],sum[2*maxn],q[maxn]; 7 ll n,minn,ans,head,tail; 8 int main(){ 9 cin>>n; 10 minn=2147483647;head=1;tail=0; 11 for(ll i=1;i<=n;i++) cin>>val[i]; 12 for(ll i=1;i<=n-1;i++) val[i+n]=val[i]; 13 for(ll i=1;i<=2*n-1;i++) sum[i]=sum[i-1]+val[i]; 14 for(ll i=1;i<=2*n-1;i++){ 15 while(head<=tail&&max(i-n+1,(ll)1)>q[head]) head++; 16 while(head<=tail&&sum[i]<=sum[q[tail]]) tail--; 17 q[++tail]=i; 18 if(i-n+1>0&&sum[q[head]]-sum[i-n]>=0) ans++; 19 } 20 cout<<ans<<endl; 21 return 0; 22 }
错误的，不知道
1 #include<iostream> 2 #include<cstdio> 3 using namespace std; 4 typedef long long ll; 5 const int maxn=1e6+7; 6 ll val[maxn],sum[2*maxn],q[maxn]; 7 ll n,minn,ans,head,tail; 8 int main(){ 9 cin>>n; 10 minn=2147483647;head=1;tail=0; 11 for(int i=1;i<=n;i++) cin>>val[i]; 12 for(int i=1;i<=n;i++) {sum[i]=sum[i-1]+val[i];if(i!=n) sum[i+1]=sum[i];minn=min(minn,sum[i]);} 13 for(int i=1;i<=n;i++) cout<<sum[i]<<" "; cout<<endl; 14 q[++tail]=1; 15 for(int i=2;i<=n;i++){ 16 while(sum[i]<=sum[q[tail]]&&head<tail) tail--; 17 q[++tail]=i; 18 }for(int i=head;i<=tail;i++) cout<<q[i]<<" "; cout<<endl; 19 for(int k=1;k<=n;k++){ 20 while(q[head]<=k&&head<tail) head++; 21 if(sum[ k]<=sum[q[head]]) ans++; 22 while(sum[k]<=sum[q[tail]]&&head<= tail) tail--; 23 q[++tail]=k+n; 24 cout<<"q "<<head<<" "<<tail<<endl; 25 for(int i=head;i<=tail;i++) cout<<sum[q[i]]<<" "; cout<<endl; 26 } 27 cout<<ans<<endl; 28 return 0; 29 }
