只能过前60%，还在罗
1 #include<bits/stdc++.h> 2 using namespace std; 3 4 #define maxn 550000 5 #define lson rt<<1,l,mid 6 #define rson rt<<1|1,mid+1,r 7 double a[maxn]; 8 9 struct node{ 10 int l,r; 11 double s0,s1,s2[4]; 12 node(){ 13 l=r=0; 14 s0=s1=0; 15 for(int i=0;i<4;i++)s2[i]=0; 16 } 17 }tree[maxn<<2]; 18 19 node push_up(node b,node c){ 20 node ans; 21 ans.l=b.l,ans.r=c.r; 22 ans.s0=b.s0+c.s0-a[b.r]*a[c.l]; 23 ans.s1=b.s1+c.s1; 24 ans.s2[0]=b.s2[0]*c.s2[0]; 25 ans.s2[1]=b.s2[0]*c.s2[1]+b.s2[1]; 26 ans.s2[2]=b.s2[2]*c.s2[0]+c.s2[2]; 27 ans.s2[3]=b.s2[2]*c.s2[1]+b.s2[3]+c.s2[3]; 28 return ans; 29 } 30 void build(int rt,int l,int r){ 31 if(l==r){ 32 tree[rt].l=l,tree[rt].r=r; 33 tree[rt].s0=tree[rt].s1=a[l]; 34 for(int i=0;i<4;i++)tree[rt].s2[i]=a[l]; 35 tree[rt].s2[1]+=a[l]; 36 return; 37 } 38 int mid=(l+r)>>1; 39 build(lson),build(rson); 40 tree[rt]=push_up(tree[rt<<1],tree[rt<<1|1]); 41 } 42 void update(int rt,int pos,double x){ 43 if(tree[rt].l==tree[rt].r){ 44 tree[rt].s0=tree[rt].s1=x; 45 for(int i=0;i<4;i++)tree[rt].s2[i]=x; 46 tree[rt].s2[1]+=x; 47 return; 48 } 49 int mid=(tree[rt].l+tree[rt].r)>>1; 50 if(pos<=mid)update(rt<<1,pos,x); 51 else update(rt<<1|1,pos,x); 52 tree[rt]=push_up(tree[rt<<1],tree[rt<<1|1]); 53 } 54 node query(int rt,int ql,int qr){ 55 if(ql<=tree[rt].l&&qr>=tree[rt].r)return tree[rt]; 56 int mid=(tree[rt].l+tree[rt].r)>>1; 57 node ans; 58 if(ql<=mid)ans=query(rt<<1,ql,qr); 59 if(qr>mid)ans=push_up(ans,query(rt<<1|1,ql,qr)); 60 return ans; 61 } 62 int main(){ 63 int n,m,x,y,op; 64 double z; 65 scanf("%d%d",&n,&m); 66 for(int i=1;i<=n;i++) 67 scanf("%lf",&a[i]); 68 build(1,1,n); 69 for(int i=1;i<=m;i++){ 70 scanf("%d",&op); 71 if(!op){ 72 scanf("%d%d",&x,&y); 73 node fnl=query(1,x,y); 74 printf("%.2lf ",fnl.s0+fnl.s1+fnl.s2[3]); 75 } 76 else{ 77 scanf("%d%lf",&x,&z); 78 a[x]=z; 79 update(1,x,z); 80 } 81 } 82 return 0; 83 }