Tree array single point update and interval query

Here is the most basic operation.

Single-operation time complexity O (logn), Spatial complexity O (N).

1#include <fstream>2#include <iostream>3#include <cstdio>4 5 using namespacestd;6 7 intn,m;8 inta[100002],tree[100002];9 Ten voidBuild ();//Array of achievements One intReadintPOS);//the answer to Sum[1,pos] A voidUpdateintPosintVal);//Add A[pos] to v -  - intMain () the { -     //freopen ("d:\\input.in", "R", stdin); -     //freopen ("D:\\output.out", "w", stdout); -     intbo,t1,t2; +scanf"%d%d",&n,&m); -      for(intI=1; i<=n;i++) +scanf"%d",&a[i]); A build (); at      for(intI=1; i<=m;i++) -     { -scanf"%d%d%d",&bo,&t1,&T2); -         if(bo) - Update (T1,T2); -         Else inprintf"%d\n", read (T2)-read (t1-1)); -     } to     return 0; + } - voidbuild () the { *tree[0]=0; $      for(intI=1; i<=n;i++)Panax Notoginseng     { -tree[i]=A[i]; the          for(intj=i-1; j>i-(i& (-i)); j=j-(j& (-J ))) +         { Atree[i]+=Tree[j]; the         } +     } - } $ intReadintPOS) $ { -     intans=0; -      while(pos>0) the     { -ans+=Tree[pos];Wuyipos-=pos& (-POS); the     } -     returnans; Wu } - voidUpdateintPosintval) About { $      while(pos<=N) -     { -tree[pos]+=Val; -pos+=pos& (-POS); A     } +}

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Tree array single point update and interval query