线段树模板

#include"cstdio"
#include"iostream"
#include"cstring"
#include"algorithm"
using namespace std;
#define MAXN 50005
int tree[(MAXN<<2)+10];

void build(int node,int left,int right)     //建树
{
if(left==right)
{
//tree[node]=1;             //初始赋值1建树
scanf("%d",&tree[node]);    //输入赋值建树
}
else
{
build(node<<1,left,left+right>>1);          //构造左子树
build((node<<1)+1,(left+right>>1)+1,right);     //构造右子树

//回溯时得到当前node节点的线段信息
tree[node]=tree[node<<1]+tree[(node<<1)+1]; //求和
//tree[node]=max(tree[node<<1],tree[(node<<1)+1]);  //求最大值
//tree[node]=min(tree[node<<1],tree[(node<<1)+1]);  //求最小值
}
}
void update(int node,int left,int right,int pos,int data)       //更新
{
if(left==right)
{
tree[node]=data;        //赋值更新
//运算更新，如 tree[node]+=data;
return;
}
int mid=(left+right)>>1;
if(pos<=mid)
update(node<<1,left,mid,pos,data);
else
update((node<<1)+1,mid+1,right,pos,data);
tree[node]=tree[node<<1]+tree[(node<<1)+1]; //求和
//tree[node]=max(tree[node<<1],tree[(node<<1)+1]);  //求最大值
//tree[node]=min(tree[node<<1],tree[(node<<1)+1]);  //求最小值
}
int query(int node,int begin,int end,int left,int right)        //查询
{
int p1,p2;
if(left>end || right<begin)
return -1;
if(begin>=left && end<=right)
return tree[node];
p1=query(node<<1,begin,begin+end>>1,left,right);
p2=query((node<<1)+1,(begin+end>>1)+1,end,left,right);
if(p1==-1)
return p2;
if(p2==-1)
return p1;
return p1+p2;       //求和
//return max(p1,p2);    //求最大
//return min(p1,p2);    //求最小
}

#include"iostream"
#include"cstdio"
#include"cstring"
using namespace std;
const int MAXN=100000;
#define LL long long
LL tree[(MAXN<<2)+10];
LL mark[(MAXN<<2)+10];
void build(int node,int begin,int end)  //建树
{
mark[node]=0;//标记初始化
if(begin==end)
{
scanf("%lld",&tree[node]);
}
else
{
build(2*node,begin,(begin+end)>>1);
build(2*node+1,(begin+end>>1)+1,end);
tree[node]=tree[node<<1]+tree[(node<<1)+1];//pushup
}
}

void pushdown(int node,int left,int right)  //延迟更新
{
if(mark[node])
{
int mid=left+right>>1;
mark[node<<1]+=mark[node];
mark[(node<<1)+1]+=mark[node];
tree[node<<1]+=(mid-left+1)*mark[node];
tree[(node<<1)+1]+=(right-mid)*mark[node];
mark[node]=0;
}
}
void update(int node,int begin,int end,int left,int right,LL data)  //更新
{
if(begin>right || left>end)
return;
if( left<= begin && end<=right)
{
tree[node] += (end-begin+1)*data;
mark[node]+=data;
return;
}
pushdown(node,begin,end);
int mid=(begin+end)>>1;
update(node<<1,begin,mid,left,right,data);
update((node<<1)+1,mid+<
4000
span class="hljs-number">1,end,left,right,data);
tree[node]=tree[node<<1]+tree[(node<<1)+1];
}
LL query(int node,int begin,int end,int left,int right) //查询
{
if(begin>right || left>end)
return 0;
if(begin>=left && end<=right)
return tree[node];
pushdown(node,begin,end);
int mid=(begin+end)>>1;
return query(node<<1,begin,mid,left,right)+query((node<<1)+1,mid+1,end,left,right);
}