【模板】树状数组

现在来填坑，之前落下的知识，现在往回补。之前一直用线段树来顶树状数组和st表，但是跑得慢，写的也慢。。。

单点修改，区间查询：

#include<iostream>
#include<cstdio>
#include<cmath>
#include<ctime>
#include<queue>
#include<algorithm>
#include<cstring>
using namespace std;
#define duke(i,a,n) for(int i = a;i <= n;i++)
#define lv(i,a,n) for(int i = a;i >= n;i--)
#define clean(a) memset(a,0,sizeof(a))
const int INF = 1 << 30;
const int N = 300005;
typedef long long ll;
typedef double db;
template <class T>
void read(T &x)
{
    char c;
    bool op = 0;
    while(c = getchar(), c < '0' || c > '9')
        if(c == '-') op = 1;
    x = c - '0';
    while(c = getchar(), c >= '0' && c <= '9')
        x = x * 10 + c - '0';
    if(op) x = -x;
}
template <class T>
void write(T x)
{
    if(x < 0) putchar('-'), x = -x;
    if(x >= 10) write(x / 10);
    putchar('0' + x % 10);
}
int n,m;
int tree[2000000];
int lowbit(int x)
{
    return x & -x;
}
void update(int x,int y)
{
    while(x <= n)
    tree[x] += y,x += lowbit(x);
}
int getsum(int x)
{
    int tot = 0;
    while(x > 0)
    tot += tree[x],x -= lowbit(x);
    return tot;
}
int main()
{
    read(n);read(m);
    duke(i,1,n)
    {
        int a;
        read(a); update(i,a);
    }
    while(m--)
    {
        int a,b,c;
        read(a);read(b);read(c);
        if(a == 1)
            update(b,c);
        else
        {
            printf("%d\n",getsum(c) - getsum(b - 1));
        }
    }
    return 0;
}

区间修改，单点查询：（用到了差分思想，注意读入，然后直接查询就是答案）

#include<iostream>
#include<cstdio>
#include<cmath>
#include<ctime>
#include<queue>
#include<algorithm>
#include<cstring>
using namespace std;
#define duke(i,a,n) for(int i = a;i <= n;i++)
#define lv(i,a,n) for(int i = a;i >= n;i--)
#define clean(a) memset(a,0,sizeof(a))
const int INF = 1 << 30;
const int N = 300005;
typedef long long ll;
typedef double db;
template <class T>
void read(T &x)
{
    char c;
    bool op = 0;
    while(c = getchar(), c < '0' || c > '9')
        if(c == '-') op = 1;
    x = c - '0';
    while(c = getchar(), c >= '0' && c <= '9')
        x = x * 10 + c - '0';
    if(op) x = -x;
}
template <class T>
void write(T x)
{
    if(x < 0) putchar('-'), x = -x;
    if(x >= 10) write(x / 10);
    putchar('0' + x % 10);
}
int tree[500010],n,m;
int lowbit(int x)
{
    return x & -x;
}
void update(int x,int y)
{
    while(x <= n)
    {
        tree[x] += y;
        x += lowbit(x);
    }
}
int query(int x)
{
    int sum = 0;
    while(x > 0)
    {
        sum += tree[x];
        x -= lowbit(x);
    }
    return sum;
}
int main()
{
    read(n);read(m);
    int lst = 0;
    duke(i,1,n)
    {
        int a;
        read(a);
        update(i,a - lst);
        lst = a;
    }
    while(m--)
    {
        int opt,x,l,r,z;
        read(opt);
        if(opt == 1)
        {
            read(l);read(r);read(z);
            update(l,z);
            update(r + 1,-z);
        }
        else
        {
            read(x);
            int tot = 0;
            tot = query(x);
            printf("%d\n",tot);
        }
    }
    return 0;
}