Another Array of Orz Pandas
题目链接：http://acm.xidian.edu.cn/problem.php?id=1187
线段树
线段树维护区间和以及区间内各个数平方和，对于每一个询问ans=(sum2-pow_sum)/2
代码如下：
1 #include<cstdio> 2 #include<cstring> 3 #define lson (x<<1) 4 #define rson (x<<1|1) 5 #define mid ((l+r)>>1) 6 #define N 100007 7 typedef long long LL; 8 struct nod{ 9 LL sum,lazy,or2zds; 10 }a[N<<2]; 11 const LL mod=1e9+7; 12 const LL Max=1e9; 13 LL n,m; 14 void push_up(LL x){ 15 a[x].sum=(a[lson].sum+a[rson].sum)%mod; 16 a[x].or2zds=(a[lson].or2zds+a[rson].or2zds)%mod; 17 } 18 void push_down(LL x,LL l,LL r){ 19 a[lson].or2zds=(a[lson].or2zds+(a[x].lazy*a[x].lazy)%mod*(mid+1-l)+2*a[x].lazy*a[lson].sum+mod)%mod; 20 a[lson].sum=(a[lson].sum+a[x].lazy*(mid+1-l))%mod; 21 a[lson].lazy=(a[lson].lazy+a[x].lazy)%mod; 22 a[rson].or2zds=(a[rson].or2zds+(a[x].lazy*a[x].lazy)%mod*(r-mid)+2*a[x].lazy*a[rson].sum+mod)%mod; 23 a[rson].sum=(a[rson].sum+a[x].lazy*(r-mid))%mod; 24 a[rson].lazy=(a[rson].lazy+a[x].lazy)%mod; 25 a[x].lazy=0; 26 } 27 void add(LL x,LL l,LL r,LL cl,LL cr,LL v){ 28 if(cl<=l&&r<=cr){ 29 a[x].or2zds=(a[x].or2zds+(v*v)%mod*(r-l+1)%mod+2*v*a[x].sum)%mod; 30 a[x].sum=(a[x].sum+v*(r-l+1))%mod; 31 a[x].lazy=(a[x].lazy+v)%mod; 32 return; 33 } 34 if(a[x].lazy!=0)push_down(x,l,r); 35 if(cl<=mid)add(lson,l,mid,cl,cr,v); 36 if(mid<cr)add(rson,mid+1,r,cl,cr,v); 37 push_up(x); 38 } 39 void query(LL x,LL l,LL r,LL ql,LL qr,LL &sum,LL &sum2){ 40 if(ql<=l&&r<=qr){ 41 sum=(sum+a[x].sum)%mod; 42 sum2=(sum2+a[x].or2zds)%mod; 43 return; 44 } 45 if(a[x].lazy!=0)push_down(x,l,r); 46 if(ql<=mid)query(lson,l,mid,ql,qr,sum,sum2); 47 if(mid<qr)query(rson,mid+1,r,ql,qr,sum,sum2); 48 } 49 int main(void){ 50 while(~scanf("%lld%lld",&n,&m)){ 51 memset(a,0,sizeof(a)); 52 LL l,r,op,k; 53 for(LL i=0;i<m;i++){ 54 scanf("%lld",&op); 55 if(op==1){ 56 scanf("%lld%lld%lld",&l,&r,&k); 57 add(1,1,n,l,r,k); 58 }else { 59 scanf("%lld%lld",&l,&r); 60 LL sum=0,sum2=0; 61 query(1,1,n,l,r,sum,sum2); 62 printf("%lld ",(sum*sum%mod-sum2+mod)%mod*500000004%mod); 63 } 64 } 65 } 66 return 0; 67 }